Should I tell her? Or just wait and let it hurt until it can't hurt anymore?

I am genuinely and wholeheartedly in love with a girl who has a boyfriend, before you judge me hear me out. I didn't knew she had a boyfriend. Though, she talked about him earlier, she use to refer him as friend. maybe she was not comfortable disclosing this since we were not close at that time, but slowly we came closer she got comfortable and she told me about him. But now I'm already in love we have spent too much time together. I think she knows this, but neither has she cut me off neither does she cross her limits, neither have I done or said anything that might make her uncomfortable but I'm sure she knows I have feelings for her. I've not told her this directly should I? It hurts that I can't even tell her that I'm in love with her. I know best advice would be to run away right? But I can't since we work together and see each other everyday and also we are in same team and very close to each other we are on calls for hours even when not required. We just sit on calls hardly talking. she's working in backgrounds I'm working in background. Now slowly I have started to feel disgusted of my self for being in love with someone who's already in a relationship but I just feel like talking to her all day, getting to know her more and more, and everyday my love for her is increasing what should I do? Sometimes not being able to confess hurts so much I feel like dying.

Should I tell her? Or just wait and let it hurt until it can't hurt anymore?
Post Opinion