Best friends , lovers , nothing , I don't even know anymore :(

[Confused child]

So me and my best friend have known each other for nearly two years now! 6 months ago I was confused whether or not I should tell him that I love him and I'm falling for him or not. Since then a lot has happened.
He went on a holiday with his family and there he said he missed me a lot , although he's sort of speaking to a girl and getting to know her , but instead of thinking about her , all he could do while there was think about me , message me , call me , coz not speaking to one another for more than a couple of hours is unbearable for us. I missed him a lot too and could actually feel his absence. While at the holiday he got in an argument with his sister who said he doesn't have his priorities sorted , he shouldn't be concerned about me but this other girl he's getting to know and kind of likes... He didn't know what to say , he told me for the first time after he came back that he's in love with me but obviously can't tell his sister about it so he stayed quiet when she confronted him during the holiday.
After he told me how he felt I admitted I loved him too ... We both knew we loved each other a lot and would do anything to spend the rest of our lives together ! Everyone who knows us tells us that we're perfect for each other .. The only issue is me and him can never get in a relationship , because of our religions. We both come from very different religions and we know marriage will not be an option for us as our families would never agree. Although part if me still wanted this relationship regardless of how long it lasts due to religion barriers but he was sure to not ruin our friendship for something that can't last forever. We agreed that we'll always be best friends and he said how he'll always love me , and the reason he's seeing this other girl coz she distracts him from thinking about me.
This distraction girl is pretty much a replica of me , she looks , walks , talks , acts , laughs , responds , just like me ! She is very similar to me in all aspects , look wise and personality , so needless to explain them to get along really well. This is the same girl he should have been thinking about on the holiday but instead was wishing to be with me.
These two belong to the same religion and she likes him too.
So now it's been literally a month since he told me he loves me , but he can't be with me , and he likes this girl too and can end up being with her ... And I told him to go for it and pursue things with her. After their second date today , being his best friend he told me how it went , and he said he's falling in love and how well she understands him and how she makes him smile and knows what to say.
How could he move on this quick is beyond my understanding !
Just last month he kept telling me to admit my love for him and couldn't stop telling me how much he loves me. Just yesterday we met and he was hugging on to me and being very physically close like I'm his girlfriend and today after his second date with her he's telling me how he loves her.
I'm totally confused and don't understand him. It's harder for me coz I do actually still love him and don't know how to handle this situation ?
What do I do ? What does he want ? I'm really confused

[namemyname]

Are you in your teens?

This guys seems to fall in and out of love pretty quickly.

[Wakeup]

While at the holiday he got in an argument with his sister who said he doesn't have his priorities sorted , he shouldn't be concerned about me but this other girl he's getting to know and kind of likes...

She's right. . . And, that is what he is doing so you shouldn't keep letting him come over and hug you and you shouldn't be allowing him to talk to you about her. Stop all contact with him now and when you'lre over missing him, find someone of your own religion and let him hug you and talk to you for hours on end.