An engaged man lied to me

I DO A DEEP INVESTIGATION without them knowing when they give me their number... long story short, social media said he had a girlfriend. I sent him the evidence, and asked if he did and he said no. Then he made his Instagram account private. I felt bad and thought "maybe he broke up with her or something". I texted him a few weeks after, and asked to hang out. Well, all ended with a blow job. I regret it, though. Very disappointed and disgusted. Well, I made more research because I wanted to block him everywhere for this not to repeat again... I found out he was ENGAGED. Like, he denied the girl as a girlfriend but he was actually engaged and I did not know this until AFTER the blow job. I felt very bad for myself, but more because the girl probably trusted him. I don't know. Well, a few months after, he was still in the app with a new profile. BLOCK. But, he was still there! 

It's been three months or more now and I saw my friend suggestions on Facebook and there he was, but how?! I blocked him!. It was a new one, and he had the "in a relationship" status. I was so confused I unblocked him on the old Facebook and saw that even the woman confirmed they were separated, so maybe he has a new girlfriend?. I don't know if it was because of me, or because another woman, or multiple... but I feel bad about myself and also feel bad for him for lying to both of us. If I would've known he was engaged I wouldn't have ever text him.