If any partner withholds sex from the other partner without putting any work and effort towards resolving whichever situation makes it difficult for them to engage, then that is definitely a reason to end the relationship. Sex is an essential part of a healthy and fulfilled life.

No, she does not have a sexual responsibility to the man The man is free to leave the relationship because they're not sexually compatible

Of course he is, purposefully withholding intimacy is a valid form of emotional abuse

Sex is a basic need. It's emotional abuse to withhold sex for longer than a short-term condition might last.

In my first marriage and first divorce our marriage counselor said there is no right or wrong reason to get a divorce. I am twice divorced and sexual incompatibility was a significant reason for both divorces. My second wife did not enjoy or want sex after she went through menopause. Oddly, she said I could have gay sex but not straight sex because she did not think I would leave her for another man. My first wife was clinically diagnosed as fridged and never had an orgasm.

I believe so, I think men tolerate too much from women.

If it's before marriage then it doesn't matter. If it happens during marriage then the couple needs to figure it out. Only reason to divorce would be if someone cheated.

He should ABSOLUTELY leave and can leave for the rain or others. Side Note: If she's withholding sex for more than a week and you've tried to genuinely fix whatever "issue" may have been the cause, she's getting it elsewhere.

Sex is what divides a friendship from a romance. If one partner is dissatisfied with the sexual aspect, the relationship will fail, sooner or later. Hopefully the partnership is strong enough to make exceptions for involuntary separations of distance like military deployment, or health issues. But even then, there may be accomodations that need to be made to maintain the marriage. You cant expect anyone to go without sex for years on end; that's unreasonable and selfish.

Its all about boundaries and communication both are justified in leaving over the matter.