Gosh, this isn't a science symposium. Why not just say horny?
He may seem super dee dooper horny because he's gone without for so long. It's like starvation. If you don't get to eat enough for weeks, months, years on end, it gets to where all you can think about is food. Likewise with sex. If he's been deprived for years, he may become seemingly obsessed. Once he is on a regular diet he may feel satisfied with X number of times a week, after a while of gorging himself.
I am glad he has this gf as an outlet for now. I hope he can keep her once you 2 are reunited, or find another partner asap.
Also, another way I relate. My gf can go through periods of times where she doesn't want sex, just cuddles. She is also a nudist and is usually naked when we are alone together. So, I see her adorable nakedness, and she hugs, kisses, flirts, and snuggles me for hours on end, I get more and more turned on, more and more frustrated. It sucks to have to masturbate when she is in the next room and can't or won't come and help me out. It sucks when I desire her so bad and I feel undesired and undesirable half the time we are together.
Now, I do have this super horny bf and we have one overnight date a week and we do a ton of foreplay, kink and fucking. Thank god. I still get frustrated w gf a lot though, the rest of the week!
Love withers under constraint; its very essence is liberty. It is compatible neither with envy, jealousy or fear. It is there most pure, perfect and unlimited when its votaries live in confidence, equality and unreserve. -- Shelley
Mags (poly, F, 61) loving miss pixi (poly, F, 39) since January 2009, living together since 2013
In a newish relationship with Steve, (33, poly)
"Master," (mono, 36), miss pixi's Dom for 3 years