I like an ex-employee - not sue of next step

I helped hire an employee just under 2 years ago. She is 29 and I am 39. From the beginning I knew I was very attracted to her personality and demeanor(she was my type). We interacted a lot. We got on well, we had a bit of a teasing relationship, and spent significant time in the car together on calls. She sometimes would say we should do this or that in a real friendly way, but I always kept my distance due to the small office and that I was one of her bosses. We shared a lot of the same views, and I know she enjoyed talking to me on a range of subjects, and we shared the same political/social views. I know she has a boyfriend that she actually lives with, but know from our conversations that she probably doesn't does share his life view, nor is her view particularly respected, and that he is not interested in more than macho male past times. In the past several weeks I know she has debated moving out - I heard through the grapevine. Just this past summer we had a company retreat and we were a bit flirty - at dinner she touched my thigh, she made sure we held hands on the beach at night after we had a splash fight, and apparently there were bets that we'd hook-up. In any event, she recently had to leave our small company as she needed to get a job with better healthcare. On the last day as she was leaving in the parking lot as I was saying good bye, I said that now she wasn't an employee that it would be great to see here socially for a museum or just coffee to talk and she was very happy to hear that, but then I said "you see, I find you very intelligent and very interesting"(words that I had used to describe a day earlier as to the type of person I'm looking for), and she mid sentence, "Stop talking, you're going to make me cry", and we just stood there for a minute locked in gaze without saying anything as I didn't want to to cry. I stared at her and said "well . . ." and turned and then she got into her car and I walked back to the office. Not sure what to do now. I've met 4 women in my life that had the right combination of qualities but for timing or work reasons I never acted, but I am certain she could be the one. Not sure how to proceed - call her up, ask her for coffee - I don't want to her to slip away. At the same time I know there is an age gap, and I feel quite silly about this long crush, maybe that is all it is, but it doesn't feel like it.