Have long term boyfriend, recently strong feelings for straight female friend

So I've been with my boyfriend for over 3 years, our relationship has been pretty bad for the past year and a half. We fight often and we both have hostile feelings towards each other so much. I think about leaving him all the time and i'm sure he thinks the same about me, but every time it gets where we are about to we decide we love each other too much and feel like we would't be able to be without each other. The past 5 months or so i've been talking with and spending time with a girl coworker of mine, who has always been my friend, but just in recent months we've became closer, and now we talk every day, a few times a day. I've started to develop strong feelings for her and I always find myself wanting to kiss her and wishing that we could be more than friends. We both tell each other all the time how much we love each other and how strong our friendship is and feel that we connect on a different level than anyone else we've met. As far as I know she has no idea of my true feelings, but sometimes I wonder if she possibly feels the same way. I know she's straight and she talks about guys she's interested in often, and knows i have a boyfriend, but tells me that i should leave him and that i deserve much better and even offered to let me live with her. a conversation we had recently, she had told me that "i'm her only boyfriend and kinda like the only one i would choose for everything so i'm not even concerned about boys at the moment, not even lonely at home right now", she had sent me that after we had hung out all night until early morning. I can't tell if she just really loves and appreciates me as a friend, or if it is possible that she might be feeling the same way? And how could i get a better idea of what she is thinking without having to actually ask or say anything? I just wouldn't want to take the chance of ruining our friendship if she didn't feel the same. Or how could I say something that may drop an idea in her mind or hint or anything? i'm lost. (we're both in our late 20's also).

I would be more inclined to believe you were a lesbian (or just with this one particular woman) were it not for the fact it's in reaction to your relationship having degenerated in the last year and a half. I mean, can you hand-on-heart state that you'd be feeling this way about her had things with him still been great all this time? When emotional needs aren't getting met by ones lover and someone else starts to 'feed' you, with enough repetition it's natural to fall in love with them. That's how a lot of affairs start, as has the person concerned saying, 'I don't know how it happened, it just did'. Also, I suspect the same thing has been happening to her for the same needs-starvation reasons (Like attracts Like). But here's the rub. The last HALF of your three year relationship has been bad. Despite this, you've done nothing to extricate yourself from him yet simultaneously have done nothing to strengthen your relationship in order to escape this "ambivalence trap", as your frame of mind is known as. Meanwhile, you're hoping this woman friend will be your rescue lilypad, or at least a catalyst to bringing matters in your relationship to a head so that you feel you finally have ENOUGH clarity to know what to do (stay and work or leave). You're a prime candidate for reading "Too Good To Leave/Too Bad To Stay" because that obviously describes your relationship to a T. It's a godsend of a book and, if you order it now, will get you out of this trap faster than you can say either "Taxi!" or "What shall we do this Valentine's night, darling?" I mean, on the surface you SOUND like you're more concerned with her than him, meaning, surely the decision has already been made. But, nope. The reason you're fixated overly on her at the moment is because you're desperate to get her to where she's finally a consideration equal to your boyfriend, whereupon you hope playing Eenie-Meenie-Minie-Mo will be a walk in the park. I doubt that very much because, last fairly iffy 1.5 years notwithstanding, boyfriend will always have that 1.5 year head start on her, so it'd be a bit like trying to compare a full grown pot plant to one that is barely peeking through the soil... which is no basis for a fair comparison, is it. Read the book. There are acid test questions all the way through that provide the clarity you're so desperately seeking about whether you truly want to leave him for her or would prefer to stay and fix with him if fixing (e.g. counselling) were possible.