Guy's Behavior

Should I start to detach from my coworker?

I have known this coworker for a year, we have always got on well and I have always had a crush on him. But he is of a different religion so I have never tried to act on my feelings. Recently we have gotten really close, always waiting for eachother at the end of day, laughing together, coming to find eachother, he calls me his best friend and tells he how amazing I am. He even gave me a back massage once randomly and we have our own handshake. He also knows a lot about me that I share with noone. My feelings are definitely so strong now, but obviously the religious aspect has made me keep quiet given that he’s told me in the past he was pretty sure he’d have an arranged marriage in the future.

All was ok and I was enjoying spending time with him even with such feelings but recently a new girl started who is gorgeous and his same religion and he looks at her in such a flirty way when they talk it upsets me so much, they flirt and I can feel the connection between them :( It has put me in a rubbish mood all week and he noticed this quickly and checks up on me but I just get annoyed with him and say there’s nothing wrong.

long story short I am wondering what to do next, I don’t want this to get me down and I feel way too connected to him for this to be a a harmless work crush

there are also a lot of us at work and we are all quite close so a change between us would be noticeable as everyone knows how close we are

Updates
1 y
And also any advice for how to detach/ what to say when he notices?
Should I start to detach from my coworker?
Post Opinion