Is this weird to you?

So my bf is in a field of work where he works with almost all women. It doesn’t really bother me but I do have a little part of me that it makes me nervous bc my dad had an affair with a co worker and was on of the reasons my parents got divorced when I was young. He talks about his female cowokers sometimes when he’s talking about work which obv I know is fine and normal but a small part of me immediately goes to my past. We are out of town this weekend and I went to use his phone to send some pictures to my phone and I noticed his two female coworkers that he talks about the most are on do not disturb. All his other male co workers are not and I found that extremely bizzare. In my opinion they’re on do not disturb bc he’s hiding talking to them. If they’re talking about work, why hide that you’re talking to them..? Am I just being insecure or do I have a legit reason to be pissed bc I’m PISSED. I just don’t get why everyone else he is friends with are normal and the two female co workers are not? What do you guys think? I did read their texts and they were all about work and honestly nothing more but its idea of hiding talking to them like if you think you did nothing wrong why would it matter if their name popped up on your phone? UGH