"No one can change me, except me." -- I hear you kind Cassandra...and I think you have well defined it: if nothing about you felt loved or accepted, there's also that need to protect the foundation of your being. Changes come incrementally, we can only handle a change at a time and many times, we can't even notice how long it takes.
I think of my marriage for instance. There are things he and I won't accept as "constructive criticism" from the other - but for some reason, when heard or read elsewhere, it'll trigger something within us to say - oh, I see it now.
So even those who love us the most and mean well, are at times the ones who least have an impact on us.
Change is so hard - and it's 100% an internal choice and then decision to keep walking in that new direction until it becomes a part of us.
However Cassy -- find that grounding, find that inner being of just you being human -- like everyone around you -- and accept yourself as being worthy of love BY yourself, before you decide what and why you want certain changes.
Otherwise, your mind keeps saying: why bother - every thing is horrible, you'll never be acceptable.
That has the opposite effect of what we want to encourage, that will keep you regressing...we want you moving forward.
Much love to you - keep speaking out, keep sharing - but start with 10 things you love about yourself for every 1 thing you want to change, as a suggestion. Let's start with self-love...once you love yourself so much, you'll WANT to change bc you want to see that beautiful being SHINE!!!