about a week ago I almost cheated on my girlfriend of 18 months , I was out on the drink with my friend for the 1st time in over a year( I never drink) and ended up at a house party. at that house party I tried it on with a girl who I find completelty unatrracitive and never will , I was being sleazy and saying dirty things , she rejected me and straight after that I was so happy she did and I instantly regretted it, I love my girlfriend so much she is best thing to ever happen to me she is my 1st love and hopefully my last as I would like to be with here forever , this happened before when we 1st started going out but I only gave my number to another girl instantly regretted it and told me grlfriens strightaway about it and she forgave me , now find myself overwhelmed with guilt , I cannot stop thinking about what I have done , I wake up its the 1st thing on my mind and stays there until I go to sleep , I don't know what to do its taking over everything I think about , I am so scared of telling her thinking that she will not forgive me yet I want to tell her as we are completely honest to each other about everything she is best friend , I don't live with her but spend every weekend with her (apart from the last one) and I going to see her tomorrow and don't know what ot do?? how long will this intense guilty feeling last , how can i get over it without telling her because thte last thing i want to do is hurt her , please help me its taking over my life