Am I wasting my time?

I met this guy on a personals sight. We get along great and I've been seeing him for 2 mos. He still has his personal profile up and when I teased him about it, he said he'd paid for a year subscription. I decided to test him and had one of my friends email him. Well, he emailed back and started flirting with her, wanted to know if she could chat later. I thought we had something good going. Is he just wanting to see what else is out there? Is he stroking his ego? What?