I got married over 40 years ago and although initially my wife and I had sex all the time, it was pretty traditional: usually the missionary position and only twice did she have my cock in her mouth.
She would orgasm probably one in five times we had sex, but she said she still enjoyed it and didn't mind. We were both happy with this.
She has since passed away and I miss her deeply so masturbation plays a big role in my life especially since I discovered the Internet.
Anyway on with my stories:
Twice I saw a different side to my wife.
The first time was when I had been away on a business trip. I arrived home a day early and I wanted to surprise her. I let myself in and had a bunch of flowers to give her when I heard a funny noise upstairs. So I went up to investigate and through the crack on our bedroom door I could clearly see my wife naked from the waist down masturbating. I have never been so turned on in my whole life. She had a wild orgasm right in front of me, and I was as hard as a rock.
I crept back downstairs and then made a noise and pretended I had just come home. She came down the stairs in a dressing gown and said she was just going to take a shower. I was still very hard and as I went up to kiss her hello I opened the gown and we screwed there and then on the stairs both having orgasms. My wife's was especially wild and noisy.
The second time was a few years later when I suddenly woke up in the middle of the night and felt the bed moving. I lay perfectly still and heard the unmistakable sound of a finger squelching against a wet pussy. I could feel her movement and hear her increased breathing. By now I was fully erect but I daren't move as I did not want to spoil the moment.
Her breathing got faster and faster as did the sound of her rubbing her pussy.
Then all of a sudden I could feel her arch and let out a muffled moan. This did it for me, and without touching my cock I shot my load. I could not believe what had happened. I had to pretend I was moving in my sleep just to cover my gasping for air.
Those two occasions have given me many a self-inflicted orgasm as I remember them fondly, like right now when I finish writing.