Ex move in ? Oh no

I’ve been broken up with my ex for 9 months , due to financial circumstances I’m still living with his mom and my child. But I want my own space, I’ve been living there for about 8 years and been through to much with them.

But my ex wants to move in with me and I don’t want him too, but he keeps bringing up the idea. I explained to him that my mental health is not good right now for us to live on our on together. But he is not listening and keeps asking to live with me.

I feel like he not respecting my decisions , he wants a relationship with me again and I’m just not ready. I’m ready to be on my own. But he keeps asking to get back together. I know moving in with him will be good financially. But my heart and my mind will not accept it. What should I do ?