Although Mary Louise Parker and Billy Crudup broke up in 2003, (he left MLP for Claire Danes while MLP was carrying his child!!) they both were in attendance at a party that, according to sources visibly upset The Weeds star to see Billy with his date:  Elizabeth Reaser. 

For those of you who don’t know who Reaser is, she plays “Ava” on Grey’s Anatomy.  If you remember Ava is the girl who got a new face.

Apparently she needed to be held up as she walked out of the event.  Too much booze or Billy, who knows?  Although it has been 5 years, I guess when someone leaves you while you are pregnant for someone else it will stay with you for a while?  Don’t you think?

She was with Crudup for 7 years.

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