How do i(15F) fix myself?

I have noticed a pattern when i started dating that i am not proud of and I’m not sure how to stop it. Every time i have a crush on a guy i always end up dating him but as soon as we do start dating either they change or i lose feelings about a month in. This has caused me to have too many exes for my age(in my opinion). I currently have a bf that has started acting differently and I’m pretty sure i liked him better as a friend(check other post for info on him) but theres 2 things stopping me from breaking up with him: i don’t want ppl to see me as a hoe or someone who uses men, and i also don’t want to hurt his feelings since i care for him. What do I do??