I am sort of in the same situation as the OP. Same age,but a gap of "only" just under 2 years. I had a friend,sort of (!)and we did it for about 4 years,more often than not,I couldn't cum,either with or with out bag. Before that a couple of WGs,one a regular for a couple of years and it took me about 6-7 sessions spread over several months (with bag ofcourse) that I started to cum.Think its down to relaxation and ofcourse laying off the HR before hand, pun not really intended !
Anyway the" friend " has now "moved on" and I hoping get one in over the next couple of weeks,before I reach that 2 year mark ,just hope it dont get too cold again !