hollowed, I'm sorry to read about the text your W sent to you. It's doubly painful that your W couldn't say it to your face, but chose the easy way out to tell you.
There is nothing you can do about her. She will do whatever she pleases and not care at all about the consequences.Our W's have become persons we no longer recognize.
The only course you can take now that will preserve your sanity, self respect and self esteem is to turn your attention and focus away from her and completely towards you. I know; easier said than done. It will take weeks or months of determination and willpower for you to get your mind off of her actions and onto your actions. The pain will not go away, but it will start to lessen. I know this because I am living it, as is everyone else on this board.
Make deliberate decisions to get out of the house and do something; anything. Be around people who love you and support you, but do not feed your angst. And I'd cut communication with the BIL; that's just causing you more pain.
Post often; being here among friends helps; there is some comfort in knowing that you're not alone in this.
H 56 W 48 D27,S21 SS25 SS22 Severely autistic M(#2 for both) 9 1/2 yrs. "I've never loved you" 3/7/2011 Separated 8/7/2011 BITS