I can't understand the concept of wanting to have sex regardless of circumstances. Is it something one MUST do?? I get wanting sex 24/7 during teens, 20's and even early 30's, but it's natural for the sex drive to slow down. This isn't a paid job, we don't get an award for having an orgasm.
I can have sex with my SO at any given moment, but won't force myself to do it when I don't feel it. Having sex with SO feels like a chore quite frankly, because it's very routine with very little excitement. Women get comfortable in a relationship, lose their sex appeal and aren't that invigorating to have sex with. It's more of an obligation now than an enjoyment.
Having sex with a beautiful young lady is a lot more fun, but even that gets old after a while. It's all very repetitive and once in a bit the experience can be a negative one and a turn off. Meeting new SP doesn't set off mental fireworks anymore as it once did, during beginner's hobby days. I accept it and wait for the time when I DO get that scratch. Doesn't meet I'm in a rut. Simply means I'm a grown boy now.