yeah i'd agree with that last paragraph. The way you describe her she seems emotionally crippled for some reason and deeply wounded which is sad for both you and your mum.

If she hasn't been capable of showing love its not your fault. I hope you can see that. It sounds like she wants to work at healing what sounds like a dysfunctional family which sounds like a positive step to me.

I pray you get to a place where you can all forgive and heal.