Originally Posted by BetrayalBtCamp
Really it doesn't matter whether she is having an emotional affair, a physical affair (or combo) or no affair with her ex at all. What matters is whether or not that is an acceptable thing for your gf to be doing. It's no different if she were a binge drinker & was good for several months then went on a week or two bender repeatedly.
She will either acknowledge it's a problem & stop or not. If not, you get to decide if you want to live with that or not.
Granted, your sexual tastes are apparently being satisfied with her so you hate to have the search process start all over again for someone that you match with so well, but if she wants to keep her ex in her life & you want the sex, making an agreement to be a no strings FWB deal sounds like a better one than the frustration & issues you are dealing with now. And from the pattern she has now, she'll be on your couch every couple of months for a couple of weeks anyway if you miss her company & wanted to let her just hang out the way he's doing, seems like.