We broke up 6 years ago. I was in my 20s and he was in his 30s and We were in a relationship for a little over 4 years. He’s been married to a woman since 2021 . Me and him we were best friends for many years before we got in a relationship which is why we ended up getting together because we worked so well as friends but then we decided we actually didn’t work well in a relationship and we were better off as friends, but that’s not the reason we broke up. He ended up dumping me after the second time I cheated. I won’t make a whole paragraph about the ins and the outs of what lead to me cheating and things. I just know it was a horrible thing to do. I’m not even going to justify my actions. What I did was absolutely horrible and I take full responsible for the relationship ending. He forgave me the first time I cheated but the second time I slept with another man and he dumped me for good and we never got back together after that. 
Fast forward to present day I get a random message from him out of the blue pretty much asking how I’m doing and we have discussions about how our life has been over the years hair catching up, we decided to be friends again. He lets me know he’s married but thinking about divorcing her Thinking about getting a divorce. I just want to be there for him as a friend 
Especially if he going through a hard time . 
There are no feelings on either end. We both are over each. It’s strictly platonic . We obviously are never going to get back together . We realized we just should have stayed friends all along 
He called me as well telling me he moved out and is filing for divorce because him and his wife can’t stop fighting and she hit him and that was his breaking point 

Is it okay to be friends with my married ex boyfriend as long as we don’t hang out and are respectful ?