Breakups

First Miley Cyrus' engagement ring returned ... now Liam Hemsworth is back -- but whether their engagement is back on is the big question, and we posed it directly to Liam.

Hemsworth arrived at LAX last night after a THREE WEEK trip to Australia and the Philippines ... sans Miley, and on the heels of rumors he and January Jones had a fling.

We asked Liam about everything from Miley's disappearing and reappearing diamond ring ... January (the month and the chick) ... and even the quality of gnar Down Under.

Miley Cyrus sent a message to her fans -- and possibly her MIA fiancé Liam Hemsworth -- by showing her enormous engagement ring is back where it hasn't been for a while ... on her hand.

Miley posted a photo of herself -- in a unicorn onesie, by the way -- prominently featuring her left hand weighted down by her diamond rock.

As everyone's heard by now ... Miley and Liam have allegedly broken off their engagement. He's been with family in Australia -- and she's been spotted all over town sans ring.

Didn't take long for Julianne Hough to come down with a case of post break-up hotness ... 'cause Ryan Seacrest's ex-GF was SMOKIN' during a night with girls this weekend ... and TMZ has the footage.

Hough -- along with her brother Derek and former old "Dancing with the Stars" pal Maksim Chmerkovskiy -- kicked it outside Beacher's Madhouse at the Roosevelt Hotel in Hollywood this weekend ... just days after calling things off with Seacrest.

Judging by her tight, short dress ... it seems Julianne is on a mission to rebound.

WNBA legend Chamique Holdsclaw insists she's no violent gun-slinging psychotic ex-girlfriend ... pleading not guilty to aggravated assault after allegedly firing a gun inside her ex-GF's car.

Holdsclaw entered the plea in Atlanta this morning -- also pleading not guilty to criminal damage in the first degree, criminal damage in the second degree, and possession of a firearm during the commission of a felony.

Holdsclaw -- who's currently free on bond -- was charged with the laundry list of crimes last month.

We broke the story ... Holdsclaw -- considered one of the greatest players in WNBA history -- was arrested in Atlanta last year for a violent encounter with ex-girlfriend Jennifer Lacy.

With all the rumors swirling that he and Miley Cyrus have broken off their engagement, Liam Hemsworth fled to his native Australia to be with the only woman that can ever really understand him ... his mom.

With Miley back in the states, the 23-year-old "Hunger Games" star showed off his ripped guns while out shopping with mommy on Wednesday.

Speculation about the demise of their relationship has been rampant ever since Liam was spotted in the back of a car with actress January Jones and further fueled when Miley was spotted without her engagement ring last week.

Another theory is that Miley was just too crazy for him and he broke it off.

While no official word from either of their camps, Liam knows there's nothing like a mother's love.

Selena Gomez just appeared in a video dancing to the song "Everybody Knows (Your Boyfriend is a Douchebag)" ... which begs the obvious question ... is this a message directed at her ex-BF Justin Bieber?

Selena and her friends post videos like this all the time -- dancing to other people's songs -- but the timing of this one seems suspect, considering Bieber's recent wave of d-baggery.

It's possible Selena and her friends just like the tune ... and there's no hidden meaning ... but Justin and Selena have been known to communicate through song.

You'll recall JB sang "Cry Me a River" at a concert after they broke up. Selena later responded by performing the same song.

So we gotta ask ...

If Selena Gomez was trying to find a way to make Justin Bieber REGRET breaking up ... this hot red outfit will probably do the trick.

Gomez -- and her butt cheeks -- were hanging out in Palmdale, CA this week ... where word on the street is that she was shooting a new music video.

Muy bien.

He basically MADE HER CAREER ... but Elisabetta Canalis feels no obligation to root for her ex-boyfriend George Clooney ... telling TMZ she was hoping he LOST at the Academy Awards.

Elisabetta was out partying in L.A. Saturday night -- when she dropped the truth bomb, revealing that she wasn't pulling for Clooney's "Argo" to win the Oscar for Best Picture.

Instead, Elisabetta -- who dated Clooney for 2 years -- told us, "Tarantino ... I LOVE TARANTINO!"

Back when they split up in 2011, George and Elisabetta released a joint statement saying the split was "very difficult and very personal."

Hugh Hefner's new bride Crystal Harris is lucky she's alive ... because Hef's old GF Kendra Wilkinson says she wanted to KILL Crystal for previously dumping the Playboy mogul.

Kendra was on the Big J Radio Show in Montana this morning when the host asked about Hef and Crystal reuniting in matrimony ... and KW blew up, saying, "I got pissed off when she hurt him."

Kendra continued, "That pissed everybody off that she would just leave him and dump him, use him and abuse him." Then added, "I wanted to kill her."

You'll recall, 26-year-old Crystal abruptly ended her first engagement to 86-year-old Hef in 2011 just days before their wedding. The couple patched things up last year and eventually married on New Year's Eve.

But don't worry, Kendra's not holding a grudge -- saying she only wants to see Hef happy.

Calvin Klein's ex-boy toy Nick Gruber is pulling the plug on his planned tell-all book about his tumultuous relationship with the fashion mogul ... telling TMZ that the $375,000 payday wasn't worth it.

The 23-year-old former underwear model has been fielding several offers over the last couple months from NY publishing houses to write his memoir, tentatively titled "What Came Between Me and My Calvin." The book was supposed to blow the lid off the dirty details in the duo's love affair.

But Gruber tells TMZ he's had a change of heart and that despite the lucrative deals ($375,000 was the highest) he just couldn't pull the trigger. Gruber told us, "I decided I no longer want to do that anymore. There was a ton of interest, but I just did not want to hurt him or others. I am a good person, not a mean person."

He adds, "Love is a beautiful thing. Money doesn't matter at all."

Time to fire up the Justin Bieber/Selena Gomez rumor mill ... because Selena was spotted returning home yesterday after hanging out allllll night with the Biebs.

The on-again/off-again (to the infinity power) couple hasn't actually been seen together in some time ... and we're told this is the first time the two have seen each other in a month.

It's clear these two young lovebirds just don't know how to quit each other.

Conservatorship wonder Britney Spears is finally free ... of her $90K engagement bling.

For the first time since breaking it off with her ex-fiance Jason Trawick, the newly single pop diva was spotted in L.A. this weekend minus the huge Neil Lane 3.5 carat rock.

As TMZ previously reported, Jason didn't have to ask for the pricey bauble back as Britney returned it all on her own.

With her lucrative Vegas deal in the works, she can buy a new rock whenever she wants.

Justin Bieber isn't the only one who can belt out Justin Timberlake's classic "Cry Me a River" ... turns out his currently ex-girlfriend, Selena Gomez, has a version of her own up her sleeve.

You may remember ... back in November, after one of their numerous splits, Justin performed the JT track on stage in Boston.

Last night in New York, it was Selena's turn ... doing her own rendition at a show for UNICEF in NYC.

So we gotta ask ...

Think Jennifer Lopez was thinkin' "Gee, I'm a Dumbass" when she watched Ben Affleck -- the guy she DUMPED back in 2004 -- clean up at the Golden Globes this weekend?

We do.

Oh, the stories Jason Trawick could tell, but never will ... because TMZ has learned he signed a confidentiality agreement with Britney Spears, preventing him from ever blabbing about their relationship.

According to our sources, Trawick was approached by Britney's team when Jason signed on to be a co-conservator, which came five months after they were engaged. We're told Trawick willingly signed the confidentiality agreement, which prevents him from talking to the press about his relationship with Britney.

However, a source close to the couple tells TMZ the two are still very close and he respects her too much to ever talk publicly about their time together ... confidentiality agreement or not.

Britney Spears and Jason Trawick broke up primarily because she wanted to have more kids and he didn't ... TMZ has learned.

Sources directly connected to the couple tell us ... Britney, who is 31, loves her boys and desperately wants more kids. Jason, who is 41, is "in another place" and does not want to start a family -- although he loves Sean Preston and Jayden James. We're told the former couple argued frequently about family and this ultimately proved their undoing.

Our sources say ... there's something else -- dealing with the Britney empire wore at Jason and "took away his individuality." Jason wanted to maintain his identity and one of the ways was to expand his business by taking on more clients (he's an agent) and making more money -- this didn't sit well with Britney.

As for settling up -- we're told it's simple. There are no outstanding financial issues. Sources say the house Britney just bought -- $8.5 mil in Thousand Oaks, CA -- was purchased solely with her money and Jason has no claim to it.