['My friend Karl had a party, he invited a lot of people and I was not invited. I felt really bad.', 'That sould make me feel sad. Did you talk to him about it?', "Yes, I asked him why wasn't I invited he came up with some lame excuse."]
That's not very nice. I think it is just better to be honest, even if it might hurt.
My friends had a party and I was not invited, it made me sad.