A few things to unpick here
- When "keeping tabs" on former AP is this being done with BS present or at the very least aware? You said that you were only doing this to find out who was stalking you. Have you gained any understanding of this? If so, then stop keeping tabs. This is keeping the affairs alive. No Contact means NO CONTACT in any form, even occasionally checking out profiles, in my opinion, counts as contact.
- Why do you need social media? Social Media was a method you used to cheat. It is a prime infidelity tool. Close social media off and if really needed then create a new profile and ONLY have safe friends and family. Set the security high and ensure that and new friends as agreed with BS before accepting.
- As for telling OBS, she has a right to agency. If you told her, would this be out of spite to AP or for empathy to OBS? I think most on here would recommend telling her. For your own journey to R this needs to be done for the right reasons. Doing it out of spite to your AP suggests there is still some emotional link to him.
A few things you said raise alarm bells with me. I'm very much still struggling with my own journey to R. I am by no means a better person than I was while cheating, so this comes from a WS who is working not one who has done the work.
He said all the right things, I was weak and made terrible choices
No, no and YES. He may have said the right things, but you still chose to cheat. Saying things like this and I was weak come across, especially to BS's as excuses. Know that you made these choices and that at no time did anyone put a gun to your head. Owning it really means OWNING every action and choice that you made or did . Yes, as cheaters we manipulate people. Say what AP's want to hear, hey we hear what we want to hear from the AP too. However at any time we could have said NO.
I know it’s coming from me taking it personally, that it was a lie why he stopped and maybe I was too ugly to be his AP.
A good realisation, why do you care though? If you're fully into R then you'll not care about what AP thinks or says (another danger of social media). Do you not think that BS does not have exactly the same thoughts about you having the affair in the first place? Please break that link to AP or you'll never be free from this.
I’ve read enough to know that serial cheaters just cheat.
Yes we do. Accept the fact that you're a serial cheater as well as your AP's. Maybe he is still ongoing with his infidelity, but you and I are serial cheaters. We always will be unfortunately. Live with this and accept it. Use the pain you're feeling to make yourself a better person.
I don’t know how to handle it other than ignore it and I can’t seem to do that. I’ve admitted to my husband when I’ve looked because it triggers me out and he can tell something is wrong.
You have to ignore it. Stop looking. DO NOT go onto any account without telling BS and asking him to be there with you. It looks bad and it looks bad for good reasons. You went onto a site that facilitates infidelity, without your BS's knowledge...This is wayward behaviour. Did you only tell him because you felt bad? Feeling bad and coming clean are positive steps. Hey, we all slip, when we do, we need to be honest, so this is good. However you cannot look on these sites on your own and without prior agreement. What would BS have said if he discovered this activity before you told him?
I just don’t know how to handle the knowledge this former AP is cheating, but I’m convinced all of them just cheat until they’re found out or get an STD.
Stop caring about AP's just stop. I know it's hard, but once again your BS will find it harder and give the continued access to sites that you used to facilitate your affair and continued checking of their accounts will only hurt BS and damage R. If you've found what you need then cancel ALL accounts you used or could you in infidelity. Do it now. Don't just promise to never log on, make it so you cannot be tempted. Stop giving yourself excuses to check up on the AP's.