I've looked up my ex, and i absolutely hate him. He was emotionally financially and sexually abusive ( LDR so only verbal thankfully, ended it because it would have become physical, he admitted to doing it before) and i left him because of recurrent anal rape threats and other threats of sexual violence, and the fact he was only interested in extreme sex (bondage, roleplay, domination, in public/places he was risking getting caught etc) with no interest at all in gentle, romantic, loving sex.
I don't want to ever see or speak to him again, i wish i had reported him after we split up but at the time cyber bullying/threats weren't really seen as a crime, in the sense there were no specific laws. I thought sexual abuse only counted if it was physical (what he did was force me to sex chat with him all day every day, all one sided, refused to talk to me the day my mum died because he was sulking he couldn't make me get him off by talking about how i'd give him a blowjob etc) He deliberately hadn't given enough info to report him for his admitted sexual assault of the other girl as he didn't tell me her name, where it happened or even what year, just "in his teens".
I look him up occasionally (once every year or two) just hoping to god he doesn't have a girlfriend and hoping hes the same, living at home loser with nobody he's in a position to be able to hurt. I don't know what i'd do if he actually did get a girlfriend, but i'd desperately want to warn her. As it goes he's made his profile private so i don't see anything at all so i don't look anymore.
How do you know he's looking her up specifically when things are bad between you? It's hard to get over someone who left you when you still love them and didn't want it to end, and i honestly do believe there are people we don't get over, ever. Thats a discussion you really need to have with him, because if he would leave you for her if she gave him the option, thats not fair on you to be in a relationship with you.