Fellow majority guy friend-having woman here. I think you’re likely overthinking here, and lying to yourself a bit. You say you trust your girlfriend not to cheat, but you don’t seem to trust her to be smart enough to see when a guy is trying to “seduce” her and not fall for it.

I liked what you said about having respect for your partner. When my husband and I started dating I was very much running with the boys, spending lots of time at sports bars chatting people up, etc. I felt free to be friendly with whoever, including exes that ended on good terms, but my personal boundary was about respect. If I caught any whiff of a guy trying to slide in through the friend door or if anyone tried to undermine/sow doubt/disrespect my boyfriend or our relationship, they were gone immediately. After seeing it happen a time or two by boyfriend got much more comfortable because he really did know he could trust me.

If you’re worried about exes being friends, maybe this will make you feel better: I was always able to be so friendly with them because I was never really that interested in them romantically. It was more of a buddy that I tried dating for a second only to find it was a bad fit and we were better as friends. Most went for the friend route initially. The ones that were real friends stayed in my life, the ones that were just hoping to get back with me eventually drifted away when their best efforts only got the friend version of me. I knew what they were up to the whole time but found that just waiting them out was the best way to live drama-free. Your girlfriend could very well be using a similar strategy.