Don't feel like having sex. No stress, not on medication, not having an affair. Any other reason? Any medication to enhance sexual desire?

See below. Please contact your obgyn or primary care doctor to ascertain if there are any physical causes for your loss of libido and take things from there. Good luck!
No desire for sex. First would rule out any medical conditions that can affect libido. Then might explore ways to enhance mental intimacy as a precursor to other forms intimacy. Would evaluate medications as last resort and only after consulting your physician. .