<human>: Can you succinctly summarize the text in 1-3 sentences?

Been going out for 6 years, she has recently moved to finish her studies across the country. We're doing different things career-wise (I'm doing law, she's doing marketing) and lately I feel like we don't talk about anything except what we're going to do when we're back together for good, which feels like the same rehashed lines over and over again.

Our relationship has always been really awesome, no issues at all, but I am just starting to develop this nagging feeling that we're together out of convenience, just running through the motions, nothing new to talk about, with the added difficulty that she's away. We've been together such a while that I really can relate with the posts in the subreddit about married couples being "companions" not lovers, except I feel I can hardly talk to her about my goals, day to day, etc. 

With this backdrop, a new coworker started last December and without me looking for anything of the sort, we've been talking a lot and such and now it's clear that there are feelings on both ends. I guess the main thing is not so much physical but the fact that we can both talk about our day to day at work, our similar career goals and such. 

I have not acted on these feelings, apart from drinks here and there (which I understand is not right, but started off innocently enough) but I don't know if I can stop myself from acting much longer. 

Honestly I know the right thing is to tell my coworker that I cannot do this and to keep things professional, but I'm having a very hard time due to me hating confrontation, liking the attention, feeling like an asshole because she'll feel like crap, losing someone I really liked speaking with and actually having feelings for her. Also, knowing that she has feelings for me, I really feel like shit for not cutting her off at the first sign.

How the hell do I do this, what do I do? Please help, I really don't want to fuck up but I feel I'm going to.
<bot>: Long time and now long distance relationship, getting stale, got mutual crush with new coworker. Don't want to ruin what I have but it's really hard.