I'll make this short but I could write you a novel on this. If you want to be happy it's up to you. 3 years ago my best friend that I had known for 28 years was killed in a car accident 5 days before Christmas. I had known him since I was 2. If you don't think that's bad enough, two weeks later my girlfriend started accusing me of wanting to be with his wife. I left her right then and there. There was no truth to it and I was not about to try to defend myself, I did not have the energy for that crap. All I took was what I could fit in my car.
So in a 2 week period my best friend died, I lost my girlfriend, my house (which I was only renting, but it was what I called home) and my two cats, all over the Christmas holidays. I felt like I died too. We were so close that without him I felt like I was starting a second life on this planet. And it was a really shitty start to it. These days not much has happened for me yet. I spend almost all my free time alone. I do what I can to get out because it's the only way I can find something other than just loneliness.
I keep trucking along, never give up hope. The way my life turned so bad in just the blink of an eye can work the other way too. Tomorrow I might find something that will return me to a comfortable life again. If you just sit around feeling sorry for yourself it's all you'll ever do!
You could also be a starving kid in Africa, And I'm betting that's way worse than your life!
What would make your girlfriend think you wanted to sleep with your friend's widow? Was she the jealous and insecure type?