I think if you had such a good time with him and now he's changing his direction, then why don't you just think about all the good memories and be happy that you were able to have all those emotions and feelings.....and that shows you're still be able to find love.....Probably, he was just a helper here to show you there is possibility to fall in love....
And you never know.....he might come back to you again....or you will just meet somebody else....
Just for time being, try to stay cool and relax.....try it....you can do it....
with love
marjan