How do I (25m) get over being insecure about my fiance (24f) talking about other guys from work?

Some background, things like this didn’t really bother me until half a year ago when I found out my fiance had sexted another guy for 4 months at the beginning of our relationship.

We have children, we’ve been together almost 4 years, I love her, and I know she loves me so I’ve been doing my best to work through the mentioned cheating especially since to my knowledge it wasn’t physical and she stopped of her own accord. But I’ve definitely beat myself up about it all with the whole loss of trust, betrayal, etc.

But, as the title says I can’t help but find myself feeling insecure and upset when she tells me stories about some of the guys she works with at a restaurant. For example she recently told me she asked one of them what his story was and then she explained it to me about where he was from, a couple crazy things he did, etc.

I feel like it’s overreacting to let something like that bother me but at the same time I don’t know how to just brush it off when we have the history of her not respecting our relationship. It just worries me and I know it’s unfair to make a big deal out of it, so what can I do?

TLDR

My fiance “digitally” cheated on me at the beginning of our relationship and now I can’t help but feel insecure and worry when she tells me about how she’s getting to know some of the guys from her work. What can I do to not blow the insecurity out of proportion?