Liam Hemsworth -- He Likes to Party, Hangin' with Mom'my

Hours after "officially" announcing his split from Miley Cyrus, Liam Hemsworth hit the town with ANOTHER woman last night -- his mother.

Liam, along with breeder of blue-eyed, Australian demigods Leonie Hemsworth, was spotted leaving the famous Chateau Marmont on the Sunset Strip together.

Earlier in the day, reps for Miley and Liam announced their engagement is off ... but offered few details as to what caused the split.

Liam didn't seem too crushed over the breakup this weekend, when he was spittin' game to Mexican singer/actress/dimepiece Eiza González in a Vegas nightclub.

As for Liam's mom -- think she's upset about the split from Miley? Or relieved?

Discuss ...