Up until recently I was really hung up about my 'best friend' driving a spike between myself and my girlfriend so that he could date her himself. I hated him, I hated her and I began to hate the world. My life wasn't bad by some standards but I became depressed and had a negative outlook on life and just stopped trying. Recently, however, I decided to move on. I got in contact with them (after a year) and wished them luck. My outlook has changed now. Life isn't so bad and there's no point in holding grudges... Moral of my story - If your angry or holding a grudge, just talk to them and let it all out. You'll feel better and life will begin to improve.