HCG is a must for long cycles to keep the boys running. It won't necessarily increase your sex drive if you're already using test, but it should increase your ejaculate volume if you are currently experiencing testicular atrophy which likely will result in a more pleasurable experience. But, like those guys said, are you running deca or tren? If so, your libido issues may have to do more with prolactin buildup or other progesterone related issues than anything else. Lowering the dose of the 19-nor won't necessarily fix your problems either. You need b-12, caber, prami or a combo of b-12 plus one of the others.
If you are only running test then HCG should be the clear answer at this point. I know myself about 3-4 weeks in on short esters my nuts start to sort of "hurt" sometimes and shrivel up pretty good. HCG starts to reverse that very quickly. My recommendation is pretty much on par with SHINE's. In the future, you may want to run it at 500 IU E4D or so starting in week 3 to avoid any issues completely. Something that can be fixed is fine, but avoiding it altogether is preferable.