Is it normal to fall in love with my best friend

Ok! So I’m here because I need to vent a little and hopefully find other people that may identify with my situation and not judge.
I’m 42, married for 17 years and we have one child who is 16.
About 10 months ago I met a girl at work who practically swept me off my feet. She’s about 16 years younger than I.
I’d been working at this company for the previous 2.5 and she joined our department around August Of 2017. It wasn’t until around October that we began bonding over a game of foosball in the company lounge. After that we began having lunch together once a week then more often. At first I thought nothing of it because all my life most if not all my close friends have been women. Might be a product of having grown up around mostly women and never having a male figure in my life growing up. Matter of fact was not even physically attracted to her then... not really my type. But our friendship grew. We bonded over so many different things. Even though we are so different in many respects we also had many things in common. She being new to the country I genuinely looked for ways to help her get accustomed to life here in Canada. I.e telling her where to get good deals on things, things about th city etc. We became such good friends that before long we were inseparable always hanging out at work. Closer to Christmas we started actually meeting up outside of work hours. We often commented on how it felt like we knew each other for ever and couldn’t believe we had only met a few short months before. She even spent New Years with the family. Between January and the end of March she went through a rough time as she was ill and required several surgeries. At this point I was already developing feelings for her and of course given her situation I stood by her during the toughest of times. We continued to bond. We have an incredible connection. It’s a spiritual connection and the truth is she helped me become more aware of my own spirituality (neither of us are religious, but we are spiritually inclined). I know that she does care about me a lot and I care about her a lot also. When I’m with her I feel the happiest I’ve been in years. She’s an incredibly beautiful person and I now find her incredibly attractive physically as well. Anyways. Long story short. I really feel that I fell in love with her. She feels like a soulmate of some kind as our connection to each other is so strong and beautiful. Other people can see the connection we have.
We have never been physically intimate. In fact we hardly ever hug or have any physical contact. But we’re connected in mind and spirit. We’ve created so many fond memories and I know there is definitely a mutual love... albeit it seems more filial on her part whereas I think I actually have a more romantic love for her. I’m torn because I’m married and While her feelings may not be the same as mine the fact is I’m in love with someone other than my wife. People tell me I should cut things off with my friend but I think I’m past the point of no return that there’s no way I can possibly live without her in my life. I love her. I genuinely, unabashedly, shamelessly and unconditionally love her. The physical attraction only began after we bonded shall we say emotionally. I love her so much that I would give up my life for her.
My wife and I had been in a loveless marriage practically since our daughter was born. Our marriage has actually improved since around April of this year. But my heart is no longer in it. I’ve stayed in the marriage because of a sense of duty and obligation. I love my wife and daughter but I’m not in love with her.
What to do?!!!