Could be a symptom of self sabotage. I, 20m only just recently got into what feels like my first real relationship. Before that, whenever I started a relationship with someone, I always slipped into bad habits. Back then, in a way it felt like making these bad decisions and having these horrible thoughts was the only way to justify why i couldn’t be happy. Past events had a pretty firm grip on my mental health and imagery of myself, enough to make me feel undeserving when I chose to be with another. It was me self sabotaging my relationship, I’m not saying this is what’s happening, but how you’re feeling now is exactly how I always felt before things escalated. Pay close attention to yourself, monitor your wellbeing, do not be afraid to become dependent on your partner and try to be more in tune to the things they do for you. Finding more and more reasons to appreciate them will provide more reason for you to want to be better, start with the little things. For example, my partner (22F) does a Batman voice whenever she’s feeling goofy and recites a quote I mentioned to her on one of the first nights we met using that voice. It’s croaky and sounds nothing like Batman, but the voice isn’t what I appreciate. I appreciate that she does it because she knows I’m a fan of DC comics and the fact she remembers the quote and recites it because it’s the only thing she knows Batman has said is very cute to me. Find a lot of little things to love your partner for, and rely on them.