I feel like a garbage person

I've been dating my bf for a little over two years. He cheated on me in the beginning, yes I was hurt, but I made the decision of staying with everything that was happening to him and wanting to do more to help him out. over a year later since that happened and he's doing extremely well. He's seeing a therapist, it's doing wonders for him and I couldn't be more proud.

here's the but part....in the most recent months, by no fault on his part, I've found myself....no longer interested in the relationship. I love him, but I'm no long IN love with him. Before we started dating I had just gotten out of an 8 year abusive relationship. My friend, his ex, while they were together were in a polygamous relationship. So I joined their little group for my jump at some fun. it wasn't bad, not something I'd do again and the two of them broke up so she could be with her newer boyfriend and so I started to exclusively date him 4 months prior to them breaking up. then the cheating happened. our little group split. we got over things. but now I have this issue. I have until Jan to figure all this out and see whether or not I want to continue this relationship. the reason being that I already feel like a garbage person for feeling this way while he's head over heels in love with me, and I just want to allow him to not have a terrible birthday, holiday, or new years. If I'm honest, I'm not happy. I don't know why or whether it stems from the cheating long ago. or maybe I should just have my time to just be single and put myself first for once since I didn't really stay single for long after my 8 year relationship. I read an article today that sort of hit home. what are your thoughts? https://hellogiggles.com/love-sex/broke-up-someone-i-love/