No Tawse (who's a man, I presume) said that because sex is so important to a man that if it isn't available, he will 'go elsewhere' which is utter, sexist bollocks.
Sex is important to most women as well as most men - no one sex has the monopoly on it. Consequently, if a sex life is poor that will be a threat to most relationships.
I've seen loads of threads on this site from women who love sex and are living in sexless relationships. Not one from a woman who thinks it's acceptable to buy it from a male prostitute though......
That's because it isn't acceptable, over and above the unacceptability of cheating.
I think focusing on 'the relationship' is a massive red herring here, in a thread where a man has been financially and sexually unfaithful with a prostitute, on top of a discovered affair. Fact is, people like this will feel entitled to look (and pay for) sex elsewhere regardless of the state of their relationship and their happiness within it.
Saying that someone who's happy in their relationship wouldn't cheat is just victim-blaming and IME quite untrue. Cheating is not always about 'happiness' or even dissatisfaction with a spouse.
It's about selfishness - and in the case of cheating with prostitutes, out and out misogyny, because a man who thinks that some women can be bought really doesn't respect or like women.