Me (19F) is in a talking stage with a guy (21M) but sometimes i get flashbacks with my ex(20M), what will i do?

My relationship with my ex was of 2.5 years and from the begining i had to ask him for everything minimum comfort don't ghost me etc but i was 16 so i thought it was this was like this the whole relationship and when i try to brk up he won't let me. Fast forward to may 2025 i broke up it was messy very messy i cried for days couldn't sleep after that when my bday came he reached out and said will change so as a dumb person i gave another chance no change after a week everything was back to normal and then i broke up again he begged gave one last chance and the last time i was so done and emotionally clocked out i blocked him on everything even upi. And now am talking to a guy who seems fine genuinely interested in wht am talking we talked till 3 am for 2-3 days but when sometimes i scroll reddit and read storys like mine I'll think omg i was there and I'll sometimes think what will i say if he came back not like i want u back but like u did this u had 2.5 years to make things work etc but the thing is even if it's negatively i Still think about him, is it bad does all people who went through a long term relationship go through this.