@Crumpled - I am the spouse of a P addict. Saw your post. I am a 55 year old man, living in the US. I was diagnosed with Low T about 5 years ago and prescribed Androgel (Topical Testosterone Gel). It worked wonders for me - The process to get my insurance to approve it is another story. So many people abuse this Rx (body building) - that insurance companies make you jump through hoops. I had to have blood drawn multiple times over several weeks before I could receive the medication. Androgel is amazing and I would become erect if the wind blew - but it is a temporary solution - it does not “reset your clock”. Hope that helps.
Testosterone is dependent on a number of things (age, lifestyle, diet, etc). And there is certainly no shortage of bullshit, pseudo-science claims that this supplement or that supplement will boost your testosterone, often with a clear "get a better boner and have more success with women" vibe. If you're concerned about testosterone levels, best thing is to talk to your doctor, who will give you a clear answer. This article and this article might help in the meantime.