Yes, I have cheated and as a result, I have a lovely 7 year old son. I don't regret having him but I regret cheating and thus ending a longstanding relationship that could have lead to the altar.
Yes, I have been cheated on. My ex-husband cheated on me (that's why he's the ex). I was angry, but then when I moved out, I had time to think about past relationships and accepted it as what goes around comes around. I cheated on a good man and then my husband cheated on me, a good woman. However, that didn't stop me from getting 1/2 and alimony!!
I haven't even thought about (let alone actually) cheating since my son was born. I know have a good man in my life and we're getting married next year. Things sometimes get boring and redundant at times, but I know now that a good relationship is not and will not be all romance and passion and sex and dinner at Olive Garden all the time. There are times when he just tells me that he loves me and kisses me on the forehead, rolls over and tells me that he's too tired for love making sometimes, and we have Meijer brand mac and cheese or ramen noodles for dinner sometimes. But he knows who's the queen, because he's the king!
When I look back, I cheated becasue I was immature. I thought that my old boyfriend was supposed to sex me up all the time, take to good (expensive) places all the time and just basically bow down to the queen

and when he didn't do that, I went looking for someone who did and I paid for it dearly! I'm blessed that my "payment" for playing around on my sig. other was my son and I straightened up my life instead of suffering in a hospital with AIDS.