TS, when you get in bed with her at night, do you think about how that dude was blowing her back out and prolly smacking her ass. Her screaming for him to go harder and harder and telling him she is about to cum all over his dikk. How she licked his ball sack and slobbed the shaft while he demanded that she deep throat it, which I'm sure she agreed to do. How he prolly busted on her face and made her leave right after he was done so she could hug and kiss up on you.
I hope this thought helps you to leave her TODAY. Get the hell out of there bro. Men aren't supposed to take a woman back after she has stepped out and let another dude marinate her sugar walls in love batter.