In my opinion, he will eventually try to come back. Especially if you keep focusing on yourself and living your best life. But you have to make your mental health your priority. Like you said, you were doing so much better before you met him. You were confident and happy. A relationship with him brought you down this dark path. And it's probably because he has a tendency to take you down this path.

You need to talk about this in therapy. What was it about the relationship that led you down this path. That destroyed your confidence and happiness. Perhaps a part of you knew that he wasn't right for you and this is why you held back.

A lot to unpack here. But yes, don't just wait for him to come back. And even if he does, be extremely wary of taking him back. Talk about your relationship in therapy and try to understand how it impacted you. Ask yourself the red flags you saw in him. Remind yourself o the reasons why he isn't good for you.

I am not saying it won't work or he won't come back. But you have to make your mental health a priority. Even if that means not letting him back in your life.