<human>: Let's call this guy John. John and I met a house party, we hooked up and started spending a lot of time together. Since he's a neighbour, we would crash at each other's place almost every day. The sex was awesome, the conversations were great, everything I could ask for in a man.

But since the beginning I knew he had a girlfriend who lives 2000 miles away. Initially, I thought of what I shared with him, as a fling, or something non-committal. But a few days passed and we bonded too well. Not just over sex, but over conversations. Two weeks back we confessed to each other that we loved being together and couldn't bear the thought of letting this go.

However, John has an obligation to marry his girlfriend whom he has been seeing for four years now, as their parents are involved too. he often apologizes for the fact that he can't get out of the arrangement that he has with his girlfriend. I know this is soon gonna come to an end because he's soon going to be engaged.

Some of our common friends have asked me to talk to his girlfriend about it. He's been having a heavy guilt-trip since the beginning of this whole thing. But both of us were in too deep to stop it. And now everything seems like a chaos.

I have been on the other edge of the knife with one of my ex boyfriend and I totally understand how the girl is going to feel about this. So now I just beed to know if I should tell her now or just let it slide?

Can you succinctly summarize the text in 1-3 sentences?
<bot>: The guy I'm seeing is soon going to marry his 4 year-long gf. Should I tell her about us?