For some, it was motivated out of retaliation.

A Harsh Lesson

"I was In the Army; I married a girl from my hometown. She kept cheating on me and accusing me of cheating, it must have gone on for 4 separate guys before I finally cheated on her."

"The reason I did it was I felt like a fool being faithful to someone who obviously didn’t care about how I felt."

"Even then when I did it; I had a stomach ache and did not feel any less of a fool in fact; I felt like a bigger one. I felt empty and hollow."

"It was when I was overseas in Korea attempting to fix things that she had a 'friend' over while we were face timing. Her replies were cold and unwelcoming even though we had agreed to work it out. She kept looking over the device and smuggly smiling at someone. I was done, over it. I didn’t speak to her again until the divorce hearing."

"A lesson well learned."

– ExistenialPanicAttac

The Three Positions

"I have been in all 3 positions."

"Been Cheated On."

"Been the Cheater."

"Been the Person Someone Cheated with."

"Almost all of them come down to insecurity, you get a sense of power, invincibility, ego boost in 2 of those 3 positions up above."

– DeadEyedAdmin

Power Play

"I've cheated because I was trying to get some of that power back. I was with someone who made me feel insecure and powerless, and someone else came along who made me feel good about myself for a little while."

– propagandavid

Mistakes made early in life can usually be more forgivable.

Young Love

"I held hands with another girl when I was in 5th grade. Very ashamed to admit that."

– JustJuiceJury

Chalking It Up To Immaturity

"I was young, immature, full of myself and lacked feelings."

–Successful_Present39

The "Player Phase"

"Same. In my early 20s, I was insecure, jealous, anger issues etc. A over all pos. I called it my 'player phase' but it was just toxic behavior. I grew up(thank god), met my gf and been together for 10 years, getting married next month. Never have and will never cheat on her. As corny as it sounds, she's my soul mate."

– skynetempire

The One Regret

"A lot of it had to do with age and immaturity I agree. If I could go back in time I wouldn’t have hurt as many girls as I did, that’s the one thing I regret. I am also dating and living with someone who I am going to marry one day. I just wish I didn’t hurt many others to get here."

– Successful_Present39

At least these Redditors are self-aware.

Not An Excuse

"Misery. Not an excuse, but it is the reason."

– CottaBird

Eventual Path To Happiness

"We hadn’t had sex in over a year. We had turned into just good friends who cared about each other but physical passion was gone. There was significant liquor involved when it happened. I feel bad about it and would take it back if I could but I can’t. I was honest about what happened and we broke up. We are still close friends and we still care about each other a lot. She has found someone else who is better suited for her than me and I’m very happy for her. In a way, it was the catalyst to us doing what needed to be done in the relationship (breaking up) to make us both happy."

– MrPrissypants13

When Compatibility Is An Issue

"Not sure if it's cheating or not but I tried to break up with my ex and she started crying and pleading with me to give it another chance which broke my heart and I reluctantly said okay. Tried again a couple weeks later because the relationship wasn't getting any better but same thing happened. She was a really nice girl and we got along well but our personalities were way too different and I wasnt willing to make her my life partner."

"I decided to go on a wilderness backpacking trip by myself to clear my head. At work I told a girl who I knew through mutual friends about it and she said she's never done a backpack trip and always wanted to, so I jokingly invited her and to my surprise she accepted and was super excited."

"During the trip we really got to know each other and I decided I would like to pursue a relationship with her. We slept in the same tent and drank whiskey under the stars but I didn't try to kiss or get sexual I'm any way because I was still technically in a relationship."

"Once we got home I broke up for good and 3yrs later we are engaged. Turns out me not trying to make any moves on her made her trust me more than any other guy and we are living a great life together!"

– byhi3

It's easy to forever peg someone as a cheater after one regrettable moment of weakness.

But based on some of the responses above, the reasons for cheating are much more complicated than you might think.

Still there are no good excuses for deceiving someone to whom you're presumably devoted.