You called it revenge, but I call it something else. You should have known that a divorced 50-year-old woman who has big boobs and a decent body would like to flirt. Especially when that person is your mom. Yeah, she went after the wealthier old gentlemen who still had a little mojo left in them, but she also liked to be playful with the younger guys too. Of course your twenty-something boyfriends were the only source of young men around, but that never really bothered you. Her flirtations with your boyfriends never were anything serious, just conversation laced with sexual innuendo and the occasional dirty dance at the club. She simply liked the attention of the younger men, but fooled around with the older ones. Or so you thought.
It was a time when you were seeing someone and your mom wasn't. Even though you were fickle about your boyfriends, you actually liked the guy you were seeing. He liked seeing your 44DD's bounce up and down as he fucked you and how you would swallow him when he came. And, even though you were a very attractive brunet with a healthy sexual appetite, his eye seemed to wander every now and then. But that didn't matter, you always tended to find something wrong with your boyfriends and break up with them anyway. However, if you were going to be together, that would've been a different story.
Then there was the night you found out about the incident with your mom almost by accident. That was the night your mom offered to take you, your boyfriend and a couple of your friends from college out to dinner before everyone graduated and went their separate ways. Mom was designated driver so the rest of you could drink - which you did. A couple of hours later, your boyfriend wasn't feeling well and your mom volunteered to take him home before he got sick right there at the bar.
"I'll take him home. The rest of you can keep on drinking." She said. Quite a bit of time later - far too long to account for the drive to your house and back - your mom returned. An offhand remark about being on the phone was made, you blew it off, and the partying continued.
About a month went by when, after an unusual sexual touchy-feely episode between your boyfriend and mom occurred, you asked if your mom had ever done anything like that before. His smirk and lack of an answer told you immediately that it had. You nearly kicked his ass getting it out of him. Then he told you about that night your mom drove him home. He stumbled in, fell on the couch and proceeded to pass out only to wake up a few minutes later to see your mom, shirt unbuttoned, deep-throating his cock. She was massaging his balls as she tried to get as much of his cock into her mouth as she could. But what really surprised you was that he didn't try to stop her. Her mouth and tongue felt so good that he held her head and began to pump his cock into her mouth. As he was about to climax he held her head to him, positioning his cock at her throat, and came. After she swallowed his cum, she leaned forward and pressed his cock into her cleavage. Pumping her tits slowly up and down around his cock she said, "I bet you're just as good in bed. Unfortunately that'll have to wait. I have to get back." And with that she buttoned up her shirt and left. About a minute after he told you what happened your relationship with him left also.
You never did tell your mom that you knew what happened, you just waited for the perfect time to embarrass her with it. Near the end of the summer she started to see someone that she thought might be long term. He was older, around 50 also, with a few gray hairs. He was tan from the many hours of free-time golf that owning your own business affords. The way your mom was always joking around and trying to embarrass him, his cock must have been larger than most. And, from the low-cut and revealing clothes he asked her to wear, he was obviously a boob man. You knew how to get her back.