<human>: Could you distill the essence of the text into 1-3 sentences?

I went out drinking with some coworkers.  After the bar I drunkenly and mistakenly went home with a coworker and this morning I woke up naked beside him.  

I have  been dating my boyfriend for over a year, and he is absolutely amazing.  I am not one to condone the use of alcohol as an excuse for poor behaviour but I know that I would never have done this if I was sober, I am not even sexually attracted to the coworker.  

I feel miserable about the situation.  I know that if my boyfriend cheated on me I would never forgive him, but I can't help but feel like my boyfriend would probably forgive me which almost makes me feel even worse about this.  

I am not sure if i should tell him.  Before this, I have always been of the belief that cheaters only tell the truth to relieve their own guilt, and that doing it because the SO "deserves to know" is a bullshit excuse.  Am I right in that thinking? Do I tell him, or just act like nothing happened.

BTW, I have told nobody about this, not even my best friend, and the coworker has agreed to also never mention this.  I do not plan on being at this job for much longer (but for unrelated reasons).
<bot>: i stupidly slept with a coworker, hate myself for it and I don't know if it would be best to tell my boyfriend or keep it a secret.