Ariel Winter -- My Mother Is DEAD to Me

"Modern Family" star Ariel Winter is throwing DISS after DISS at her birth mom ... making it clear, she wants NOTHING to do with her biological life-giver ever again.

As you know, 15-year-old Ariel has been at war with Chrystal Workman for the past year -- and even got a judge to strip her mother of custody in 2012 after claiming she was subjected to emotional abuse.

Now, Ariel is pouring salt in the wound -- by making public statements in which she makes it clear, her mother is dead to her ... and her older sister Shanelle has filled the emotional void.

When asked about her family yesterday, Winter told People.com, "My sister is the most amazing woman I've ever met in my life. If I could be half the woman she is ... she's kind of who I want to be like."

Did you catch the thinly veiled dig at her mom? If not, check out what she Instagrammed on Mother's Day:

"Happy Mother's Day to my amazing mister, Shanelle Gray. I know everyone is going to ask what a mister is, so I'll explain. It means mom/sister to me."

She continued, "She's my best friend ... She's also the most incredible mother. I am so blessed and lucky to have her."

Translation -- Ariel's over Chrystal ... and from what we're told, she has good reason. How's THAT for a modern family?