Wife has kept college friend that she slept with twice years ago. They met and had sex 7 years ago. She and I met 5.5 years ago and have been married for almost 2 years. I was aware of this relationship from the beginning, she never hid it, and I never had a problem.

Their college friend group is pretty tight. He and others came to our wedding, and they visited us when we lived on the other coast. Wife's always had a key to their apartment where a bunch of them live together. He pet sat for us, and she would crash at their place if she worked late in the city. He's a total player, but I'd hung out with him one-on-one before and it felt fine.

Our marriage has always been rocky, lots of our own issues but I never felt suspicious of her. Anyway, I'm on a 5 week business trip last November and when I come back in December she's been hanging regularly with them and crashing at their house about once a week. At this point, she is hanging with him 3 - 4 times a week, texting and snapchatting daily, way more than any other friend. Hmmmm...

At this same time, I uncover that she is looking into grad programs outside our city without me knowing. So she's making an exit plan. I confront her. I tell her the escape plan is unacceptable, she admits to it, and that goes fine. At this point, I make a connection in my mind between her exit plan and her friendship.

I tell her that I feel uncomfortable with her hanging out with him so much, hanging out alone, or staying at their place anymore. She of course defends her position, nothing happened, it was so long ago, are you jealous, you're trying to control me, etc. We agree that she won't hang out alone or go to their house, but she says he resents me for this.

Since then she has regularly thrown shit-tests at me over the last 6 months. Texting with him in front of my face after we have an argument, telling me that he slept with so-and-so, asking to hang out with the group when it's been a day since I said I'm not interested. She has brought this up at counseling; she tries to make it about me being jealous or controlling.

The accusations of jealousy and controlling seem like flack being thrown at me to make this about how I'm handling this wrong, instead of the actual problem. I don't feel jealous, just deceived. Is it controlling to limit how much your wife hangs out with a former sex partner, who is a serial player, she has a key to his apt, and she had an exit plan less than 6 months ago? Again, this seems like a reasonable boundary in marriage, perhaps even more vital in a rocky one. You could say I set up this boundary way too late, but I never viewed this as a problem until I lost trust in her.

Context matters, so in short we've both made huge self-improvements in the last year. This "friend" thing is a new issue and I'm unsure how to proceed. It comes up every few days, and it's definitely blocking any further progress in the marriage. Once upon a time I would have nuked or next'ed a relationship over this kind of bullshit. No kids. I'd like to give this a shot.

TLDR: Rocky relationship but shows potential. Wife is insisting on keeping her long-time friendship with a once sex partner.