Go talk to your doctor. Seriously. No, its not particularly normal for a guy your age to suddenly have a libido loss. Even gradual. It could be a number of things, are you on regular medication? Some can reduce your interest.
If you are into homeopathic remedies, try zinc, magnesium, there are several others that can help too.
But best to talk to your GP first, could be a hormone problem, psychological (depression, stress, worry, lack of good sleep, to name a few).

It is all in your head.


When I say that, I mean that it isn't so much a physical thing, more a mental issue.

Have you got other stresses/things on your mind at the moment?

Either that or invest in some good porn...

Offering a loan from your private library Megs?

If he is into 'interspecies erotica', I'm the man for the job....