When do you know a relationship is over?;

Wondering when you know that emotionally a relationship is over? My husband and I are having communication issues and couples therapy isn't an option for him.

I'm feeling like things are over but I'm not sure how I would know for sure?

Obvious deal breakers for me would be cheating, drugs, etc but there is nothing like that happening. Just two people who seem to be growing apart.

We spend a day a week together as date day and date night but over the last few years it's just becoming increasingly boring. We walk around Target or Walmart but we never really want to do anything together.

I like to read. He doesn't. I like to work out - he doesn't. He likes to play video games and, although I used to, I don't anymore. I'm 34 and we played together when we were in our twenties but since then I get motion sickness and eye strain so I avoid them. He doesn't want to do anything like a cooking class together or pottery class or something. The only thing really left is great sex. We have sex 3-6 times per week and it is great still. We know each other bodies really well and definitely have chemistry there still but everything else feels disjointed and disconnected.

Any advice?

Answering questions here: therapy isn't an option for him because, although, he says he will go he never follows through. He says he will make an appt and doesn't. I've made appts before and we end up cancelling because he's not feeling well or he doesn't want to leave the kids with a babysitter etc. Always an excuse. I bought a book one time called "fighting for your marriage" but he never read it.

Yes - he does struggle to voice opinions or emotions. He's not much in the way of deep emotions or root cause for emotions