(((NOWWHAT)))
Maybe you did allow those things THEN, but perhaps you didn't really know any better at the time. I don't really think you should feel shame for that. Maybe you were stuck for a while, but you bucked up and did what was best for you by leaving and for that, you should feel very good about yourself. I think we've all been able to look back and see where we made some bad decisions, but what matters is that we changed!
BTW - I don't think shame is at all useful just as I don't think worry is useful. Shame is for things in the past, which cannot be changed. Worry is about things in the future which 90% of the time never even occur.
(((HUGS)))