I ditto Ownit. Of couse, I can understand why you'd be angry. But, this whole situation is way beneath you. She is a married woman accepting gifts for her kids from her affair partner! It's insane. As Sotto says frequently, she is someone else's girlfriend now. Leave them to each other.

Look, it's pretty clear you are a good guy. Don't devalue yourself by engaging in this nonsense that has become her life. You are the prize.

Detach, focus on you and leave her to her slop of a life. You have better days ahead of you.

Me 41, H 47, M 15 yrs, S11, S13
BD 1: 11/4/14 we work on it; really I pretzel myself
BD 2: 3/31/15 H goes down to "dorm room"
8/15: H back to MBR
10/15: H back in dorm room
1/18: H files, now divorced