Can sex be spiritual even when it is not called "spiritual sex" per se? Just musing out loud.
I'd posit that it can. Sometimes it happens spontaneously.
This is in contrast to magickal sex, which by definition harnesses the will of the participants and directs the energy raised into achieving a predetermined goal.
To the OP, be wary when researching Crowley. He was an undisputed asshole, including by himself. For a contemporary, try Dion Fortune (Wikipedia is a good start).
I saw that whole list of possible belief systems... It omits mine, so please don't consider it definitive. Keep exploring. OP, If your marriage is severely hampering your spiritual growth, I'd recommend leaving your marriage. But that is because I am of a system that places spiritual growth first and foremost.