Of course. Take care of yourself - you're important and you matter.

It sounds to me like he was trying to do some shady shit on the side with an ex and got caught, and his reaction to being caught was to turn it around and break up with you... And now he's still getting all the benefits of being in a relationship with you (love, chat, care, sex, etc) but he's not formally in a relationship with you, so he could still be fucking around on the side. This is just my perspective on the situation based on the info you've shared.

It sounds like this is having a big negative impact on you. If you broke up to focus on your mental health, I think you should really do that. Stop having contact with him for now and focus on getting the care and support you need to feel ok again.

Why did you split up? That's important context that's missing here.