Am I into her? Is she into me?

At age 35 I feel kind of stupid having to ask for help in this forum. Im openly gay for over 10 yrs. I have had quiet a few relationships, only two of'em formal. Four yrs ago I met this girl into a pet owner forum, since we both are pet lovers, and we started a friendship. At that time I didn't know she was also gay. I liked her since day one, though Im really not into developing crushes into straight women. When I knew she was gay I started to develop a more deeper relationship with her, but never mention love. Was kind of just flirting. She was really nice to me, continuously sending nice messages and stuff. She said to me, she like to get to know people real well before becoming anything more than that. I absolutely agree. So we met at different pet owners activities and so. She is kind of shy, though, she has a really strong character. So, two yrs went by and I still kept there waiting for something to happen. At that time, a lot a things went wrong in my life and I decided to move out of the Country. I told her and she never believed me. She said I would never do that. Though, I did. I stay out of the Country for over a year and came back. She didnt even wanted to talk to me. She only did because of common friends we have. So, we engage together in voluntary work for pets, this time all alone. She told me she got really mad at me for leaving. She then again started sending me nice messages and songs. When we finished the voluntary job, we decided to open a pet oriented business together. We have being doing this for five months now and we have started to fight a lot, and is not for business issues, but personal. I have turn a little cold into her since nothing has happened in almost four years, I dont expect nothing to happen ever. I know for sure we both have been behaving like little girls, since I am 35 and she is 43! I have never in my hole life have found a woman so difficult to understand a please. She says the same thing about me being a "sea porcupine". Still Im pretty sure I am into her. When we fight, I only want to stop and kiss her. We both know "something" is happening between us but, while arguing we both say we don't know what it is. The only time we got close to being truth to each other, we both had a few extra drinks, but we weren't drunk. I have even blame it into astrology because she is a Gemini and I am a Pisces. But I know is not. I know for sure asking if she's into me is the answer but I really dont' want to jeopardize our business relationship and make her uncomfortable. Well, sounds pretty stupid to me and I wont judge you I you tell us to grow up. I have to admit again I have never ever had such kind of awkward relationship but for some reason I just can't let it go. I have had other partners while this is happening, and though I have never being unfaithful to a partner, it feels kind of being. My best friend says she is into me because, he says, she behaves nervously while he's around. Like if he would notice. I dont expect you to give me a solution. May be a just need to see it written in black and white to see how senseless and childish it is.