gets popcorn
Well goodness gracious me this will be messy.
YABVU obviously.
Sure the favourite response is 'they have the option of leaving before cheating', but why is the onus of leaving on the partner who's deprived rather than the one depriving. Surely if one partner decides to hardly or never have sex anymore, it should be on them to leave.
No, the onus is on the person who is not happy with the status quo of the relationship. The amount of sex within a marriage is a fluid situation based on how much sex both parties feel like/are capable of having. At certain points in peoples' (usually women's) lives they will want more or less sex, this will fluctuate on the basis of a huge number of factors (the obvious ones for mothers being pregnancy, childbirth, breastfeeding, and the exhaustion of raising early years children).
Anyone who gets married with the cast iron expectation of a fuck at least every other day on the dot is frankly deluded. It is POSSIBLE, I'm not saying it isn't, for that to be some couples' constant, but I am saying that in the same way one says 'in sickness and in health, for richer for poorer' it is implied you get married to the person with an understanding they may change, and that (assuming those changes are not 'into an abusive arsehole') you will both work to accommodate them in the relationship.
It is perfectly acceptable for people to go off sex for a while at times. 9 months pregnant in the blazing heat? Fuck off with that. 2 months PP leaking milk and locchia and tears from every orifice with a baby attached to you 24/7? Uuuuh, fuck off again. 18 months into raising a child that has never slept for more than 3 hours at a time and your partner can't or won't take any of the night wakings? I guess that gives them lots of time alone in bed with their hand.
Sex, with a particular person of your choice, spouse or not, is not a human right or a marital one. There is no set amount of sex which, if you drop below it, entitles you to lie to your spouse, break your vows and endanger their health.
You can, of course, leave a marriage for any reason you like. Including lack of sex.
But there is no promise, explicit or implicit, to provide your spouse with a set amount of sex at regular intervals. No promise has been broken in reducing or even ceasing to have sex.
But it's nice to have this insight into the reasoning of the cowardly selfish men who cheat.