bisexual female-does my friend feel the same way and what should I do?

I've known my friend since primary school. We were best friends, at each other's houses all the time,inseparable!
She came on to me once during our friendship and nothing else ever happened. As we left secondary school we lost contact for around 4 years. It was during this time that I'd come out as bisexual and entered what turned out to be a 4 year relationship with my ex gf.
During my relationship with my ex, I bumped into my old friend (this was around 6 years ago to date)and instantly fancied her! We exchanged numbers and I made excuses to txt/see her, I had all those butterfly feelings and loved everything about her. I knew nothing would happen between us as I would never cheat on my gf and well my friend, was apparently straight, in a long term relationship. Her relationship was up and down, they were always fighting, splitting up, getting back together.
I saw a lot of my friend and we become really close again. She had a baby, I was the first person she told about the pregnancy-not her ex, I was there at the births or her children-not her ex!
I split with my gf after 4 years and was in a dark place, totally devastated as she'd been cheating on me for the entire 4 years!
My friend was there and she helped me thru the worst time in my life. During this time, my love for my friend deepened and now being single,I dropped the odd hint that I liked her but she'd knock me back with something like 'well if I ever wanna go with a bird, you're the one I'd chose'
She was still on and off with her fella, and I was there for her, making her kids dinner, bathing them, putting them to bed and gave her a shoulder to cry on.
Then I met my fiance and father of my child- and my friend finally totally finished with her ex. We're inseparable and think about eachother night n day, we stay up all hours chatting n texting every single night, we spend Our days together and when we're not together we're texting n calling.she now says I had it right being with a girl n she may turn bisexual as she doesn't like men. She had one too many at a party recently n spent the night on the phone to me-telling me that she's speaking from the heart that I'm her soul mate,she loves me so much and that looking back she never really loved her ex, that it was n always has been me who's been there and that she hopes my fiance knows just how lucky he is'. The past weeks I've noticed she's been dressing up in gorgeous dresses n doing her make up n wearing more jewelry n perfume when we meet (I tell her how gorgeous she looks) recently I noticed that she can't stop this massive silly grin across her face when she's talking to me and she can't seem to maintain eye contact for as long...what does this mean?
I love my fiance and won't ever cheat on him or hurt him but the entire situation is driving me crazy, I've been madly in love with her for 6 years and my feelings and our relationship is somehow growing n deepening every day! What do I do? Do you think she does feel the same way towards me?