Is it normal to choose not to have sex.

I am a male, 22 years old. I am not a virgin and I think that I have had great lovers in the past. I get sexually frustrated sometimes, but I help myself by performing masturbation. I had a women in my bed 2 nights ago and she sexually aroused me but I didn't do anything about it making up an excuse that I was too tired to do anything. I wanted sex. But I chose not to have it. I am not insecure about my penis size.

I'm pretty sure this is not normal and I feel as though I'm the only guy out there who wont sleep with a women even if she is in bed beside me. I feel sometimes that I just want a women to look after me, and not the other way around anymore.