First time in the presence of my wife earlier this year.
I have been jacking off for a very long time now (25+ years). I had always done it while alone. Never had I even imagined jacking with someone else. Then, one morning, while laying in bed with my still sleeping wife, my erection became very sensitive. It felt like whenever I knew I had to get something or go to the toilet and relieve myself. I really wanted to roll over and wake her but it was so rare for us to sleep in. So I just reached down with my right hand and began to stroke myself while she continued to sleep. This excited me beyond anything I had felt in years. The thought of her waking up and 'catching' me was very arousing.
Well, some time during my self pleasuring, she awoke and 'caught' me in the act. It took her a moment to realize what I was doing. To my relief and excitement, she reached over and began groping me and encouraging me to continue. It didn't take long before I came on her belly.
It is very comforting to know that I can rely on this kind of self-relief with her assistance. I have since masturbated in her presence several times. It is very satisfying.