Thoughts that help me be in a relationship I know is ending?

I am in a live-in relationship with someone who has diagnosed borderline personality disorder and is emotionally abusive. I want out of the relationship but it’s not something I can do right now.

I have been trying to focus on bettering myself so I can be ready to leave when it’s time but I keep letting myself get sucked into his chaos. He runs very hot and very cold — telling me he loves me so much and then treating me like I am an awful person. I want to feel neutral when he is being mean or manic but I am having a hard time reaching those thoughts.

For instance today he called me in he morning and told me I had to get something done before 11am and he kept repeating himself and I kept saying I would do it. Somewhere along the way he thought I didn’t want to do it and started to turn mean and I got sucked into and after the call I felt a lot of resentment and hate and I allowed those feelings to rule my morning. I want to be able to feel like the way he acts does not matter to me so I can focus on me and leaving.

I wrote down these thoughts but they have not been helpful — I think because there is a % of me that still feels sad about this relationship, wishing it would have been different and maybe sorry for myself too.

— He can act however he wants to
— He does not deserve my energy
— Getting upset or hurt only hurts me
— Getting upset prevents me from using my energy on things that matter most to me
— He won’t change, stop giving him your energy

Maybe these thoughts are too far ahead and I need to work on my resistance (wishing it was different) to the situation first?

Help please.