Me: BW, age 69
My H was having ED problems with me prior to the A and so he got a prescription for Viagra. Our sex became less frequent (Viagra is expensive!), but at least it improved.
Then OW took him out for a drink after work one night and they kissed in the parking lot afterwards. He got very hard, unmedicated. They started kissing and canoodling in the office after work, after everyone else had gone home. A month later, they were having sex.
But he soon started to lose it with her as well and always took Viagra to their trysts so he could perform. He was beginning to feel guilty, and then too, the high from the fantasy was beginning to wear off.
And yes, the diminishing supply of Viagra was a major clue.
Him: WH, age 67
Married 22 years
D-Day: August 14, 2012
9 year LTA with former co-worker and family "friend"/7 years EA+PA, 2 more years EA