Who is right?

I’ve been having an online relationship with someone on Runescape for 4 years now. Today he just informed me that he is getting married and can no longer continue our relationship. Obviously I am devastated, we have been through so much together and were even talking about marriage. He says that he looked at our Runescape relationship as just a game, but I thought it was the real deal. Do I have a right to be upset and even inform his Fiancé of what he has done? We haven’t exchanged phone numbers or social media information, but I can find a way to get it.