guilt depression-too hard to cope

Last year I was going through a divorce and on a serious downhill spiral of alcohol abuse. One night I had sex with my best friends boyfriend and she has not found out. Since then not a day has gone past that I haven't thought about it and I feel it's destroying my soul. I can't even describe the level of self loathing I feel and how separated I feel to that person I was last year almost as if it was an out of body experience. Her and I are very close to this day and I can barely face her. I often want to walk away from her life and not be her friend. To make matters worse the absolute love of my life is her brother...we were not together at the time of infidelity but I still feel as though I have cheated on him. For me i know that telling her seems the right thing to do but the amount of lives that would be destroyed from the truth just seems to big of destruction just to aid my guilt. Her boyfriend like me regrets that day and is a good man it was just incredibly poor show of character for both of us. To ruin her, his, her brothers and my life not to mention how it would affect our mutual friends just doesn't seem an appropriate course of action to make myself feel better. I'm slipping into depression about it now and it gets worse each day. I feel alone as I have no one to talk to about it and I feel afraid that she would find out some other way and if it is to come out I would rather it be from my mouth. I am not a lying, sneaky, deceitful person or at least I wasn't until that day. I find it hard to look myself in the mirror not only based on hurting one of the most important relationships i've ever had but that I was actually capable of sinking so low. I don't understand how I did it and just can not cope with it. Sometimes I feel like just disappearing from everyone's life, moving and not telling anyone so that they don't have to be in the life of lying, cheat a truly horrible person. I hate myself for the first time in my life. I truly hate myself.

Hello & Welcome, K_two!
I have no confidence in my ability to address the relationship aspects of the issues you raise. I do realize that depression messes with my ability to reason, so I try to refrain from making major decisions when I'm at my worst. It may be best for you to first seek help, formal or informal, before trying to deal with the elephants in the room.

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