it’s easier to hold onto bad habits if you are ashamed of them constantly repeating the same pattern over and over again. I’m not exactly sure why, my guess is it’s because that poor self image convinces you that you deserve to live that way. But once you forgive yourself for it and hold genuine compassion for your choices your grip can finally loosen.
I think part of it is also that people often use the bad habits they’re ashamed of to deal with the shame they feel over them and it ends up a never ending cycle