Others were more humorous in their responses, with one writing that they once ate their girlfriend's leftover food and then denied it when she asked where it had gone.
They joked that they were haunted to this day by the lie.
Another shared that "the dog farts far less than he thinks she does."
One of the more serious revelations was from inappropriate_jerk149 who revealed: "That I've become a closet alcoholic due to the stress caused by a) her losing her job because of her own alcoholism and leaving me the sole burden of keeping a roof over our heads and b) helping her maintian her sobriety. The irony is crushing me."
Some were nothing short of heartbreaking. One Redditor wrote that the biggest secret they kept from their partner was: "How unappreciated and unloved I feel a lot of the time."
Others confessed to being deceptive about food and maintaining a healthy lifestyle. Adulyas3 wrote: "I sometimes sneak out or lie about what I'm doing and go get fast food or frozen yogurt without her. My fear is that someday she'll think I'm cheating and get someone to follow me, only to find out that I'm so utterly boring that even my darkest secrets are lame."
Bailey795 said: "... every night I get up and drink juice out of the container and put it back in the fridge."
And Help_im_a_potato shared: "If I'm away for whatever reason I will have a few cigs. She thinks I quit years ago but all I want is to smoke, endlessly. Like that episode of friends where chandler smokes a Carton.
Another user revealed their biggest secret was that they foud their partner boring: "... I''m pushing him more to go out and meet new people and find hobbies he's interested in, also for the sake of his mental health, but I just really don't want to be the only person coming up with ideas for activities or having friends to meet up with."
When it comes to getting trapped in a relationship of convenience, user bagonons wrote: "I started dating a girl that lives across the hall from me in my apartment building. I was going to break up with her when her lease expired this month but she decided to extend it another year. I don't know what to do."
Some also confessed to hiding money from their significant other: "I have $100k in a secret, separate account not to hide it from her but to be the hero if we ever need it in an emergency."
Or, to hiding how much debt they were really in: ".. our finances are completely separate so it's not hurting him or his credit score... I would be completely embarrassed if he knew just how often I was completely broke by the next payday. if it stay on course, I should be good in 10 months.... just paid one thing off this month, and have 8 payments left on 2, and 10 on another.. then all I will have is my car payment.. hopefully then I can start making extra payments on either his jeep or mine."
Confessions of insecurities were revealed too: "How insecure i am of not being enough for her. It bursted out twice and she confirmed i am more than enough but the feeling that she deserves better doesnt leave", wrote user TaP_patrick.
And Redditor VelvetDreamers shared: "I wear inconspicuous hearing aids and superstitiously change the batteries in the toilet or a vacant room. I'm quite disconcerted by the fact that it's a genetic disorder and if we discuss the prospect of children, it will impede his decision to commit to a family together. I'm aware it can be perceived as being deceitful..."