Have you ever had to change who you were to be with someone?

Like, when you first meet, they like/love you as you are, but then moving along in the relationship, they constantly hurt you and appologise pretexting they dont do it on purpose, that its just because they've never been with someone like you before and they ask you to give them time to *better* themselves so they wont hurt you anymore, but it never happens .... so you have to change who you are to ease the relationship on their side... like you hide the pain and hurt they cause you to try to make it work?

I always used to do that, but always ended up the hurting one in the end... why am I like this