I have been there man... Hang in there (I know that's not what you want to hear), it (mostly) gets better with time. Do anything that will keep your mind off it, it's best that way. A few years back I was devastated when I caught my GF of 3yrs sneaking around on me. What worked best for me was, ahem, getting "back up on the proverbial horse", so to speak

. I'm not saying that's the best thing to do, but it helped me

. Anyway I had blinders on for this girl and held her on a pedestal thinking nothing like that could ever happen, which I guess only made it worse.
On another note...
I currently am not using my COD4 account heavily, so we could possibly share my account until you can get some fundage together to purchase it. Let me know, and we'll try to work out the details.