He hasn’t finished during sex in over a month

Please help me. I’m not sure if I’m able to continue this relationship and not because of the sex thing. Let me explain.

My boyfriend and I have been together 6 years and have known each other over half our lives. In April, he told me he wasn’t in love with me anymore after I found out he was hiding snap chat on his phone. That led to him breaking up with me. The next day he had changed his mind? We have kids so I decided to keep trying to make things work.

In May I began asking him to start counseling. In July we did. He told me he didn’t want to do counseling because he was worried it would “bring negativity home”. After our second session he used what I said in counseling to start an argument. Last week he canceled our session without considering how I felt. He has yet to reschedule it.

A month ago Was the first time he wasn’t able to finish during sex. A week after this he started a new medication. This has been his excuse for what’s happening, even though it was started a week after the problem began.

I just can’t shake this feeling that when he broke up with me, something was going on. I’ve never felt the same about our relationship since then. Something I’ve talked to the counselor about. My bf is less forthcoming in our sessions and when asked about anything his answer is always “I don’t know”... I don’t feel like he’s trying at all.

Honestly I just want out of this relationship. I’ve tried so hard for years to make it work and he’s put in a small portion of effort into any of this. Like bare minimum (calling the counselor after months of asking him to). What would you do? Is it even worth trying or should we call it now before things get worse? Please help