How about getting with a bi guy and masturbating and sucking each other off. When my sex life dried right up and i slipped into depression, cock sucking and pulling off with someone helped me come to terms with it, and i got a lot of built up sperm out of my system. Feels amazing to be sucked off.
Now that I am in my 60s I find that my desire to masterbate still holds steady. the sessions don't last as long as they did in the past, nor do i stay hard as long. But I still enjoy it, and I think I am at a 99.5% rate of of masterbating while in the shower for the last 50+ years.