I think my bf is paying girls on Only Fans

How do I find out for sure. I saw a few emails he deleted in the last few days from Only fans saying “you have an unread message from Veronica Serrato” and yes, all from the same chick. And I saw some transactions on zelle to a Marissa Mendoza. He doesn’t have any friends by that name. How do I approach him? Or how do I find out and get proof before approaching him about it. I practically live with the guy and I’m supposed to move in soon but idk if I want to anymore.

A few days ago we had an argument and I told him to never lie to me, to be honest with me and to never make me look stupid. Idk why but my instincts were telling me he was being shady about something. I tried talking to him about it but he obviously lied to me. Now I know what it is and I’m in disbelief. 🥺💔 he keeps claiming he loves me and wants to spend the rest of his life with me but I can’t stand being lied to.