Please Help! Sorry about the length. I like this lady at my job, should I tell her or just give up?

There's this lady I work with, I'm 18 and she can't be any older than 24. She has a bf and maybe some kids. When I first started talking to her she seemed shy and barely said a word to me. I felt that I made a bad impression so I went to her desk and just started some casual talk and I got her to giggle, I built on that and eventually had her smiling and opening up. About 2 days later I went to pick something up from her desk and I thought "hey let's catch up". I then asked her about her day and she told me how she was all tired and its been long and yada yada, I then said don't get tired before our first date, obviously just kidding as this was only our second interaction, and she laughed and then said "you're so cute" I figured she was just being nice, she has a bf. The next day I came into work and she greeted me, I was surprised because she's usually quiet. Later that day I told her i'd switch my position so that we could talk more often and become better friends, she asked when would I make the move, I then said "i see you can't get enough of my charismatic charm." she then smiled and said don't get big-headed. I then lightly brushed my hand across hers and she didnt move away, just gave me a shy smile. I figure she knows I have feelings for her but doesn't want to do anything to hurt me or more importantly her boyfriend. Now I figure that since she has kids she may feel obligated to stay with her bf but is hurt inside by her relationship with him hence her seemingly sad nature when we first met, going back to the moment, after I made a physical move and she smiled, she answered my joke about moving positions earlier saying, she wanted a bonnie and clyde dynamic, besides murder and crime I think bonnie and clyde had a romance going on. She's really nice to me, she greets me, we joke and flirt, whenever there's a heavy work load she apologizes even though it's not her fault and it means alot, she's honest and caring. One day I was clocking in from lunch as she was leaving for home and she seemed really sad like sadder than I've ever seen her, I had asked her what was wrong and she said she had a headache. I left it that, but I began to wonder if something was going on with her kids or bf. She was really shooken up. I offered a tylenol for her headache and she declined saying. Her home was close by, she asked when would be the next time I worked and we talked for a quick minute. As we parted I told her it'll all be okay I'm here if you need me anytime. She then smiled slightly while saying "cute and a poet". She then left as I told her to be safe going home. And lastly, later that night I texted my friend about her and she replied with "Don't get your hopes up, I don't want to see you hurt." So I don't know what I should do. I know dating in the workplace can be dangerous, and she has a bf, and the whole time she may not have had feelings other than co-workers and friends, but there can some chance out there that she may have feelings for me, again prolly not. I just need to know if I should just come out directly and let her know how I feel regardless of the outcome or if I should just drop this infatuation. I've given loads of that about the good an the bad outcomes and rejection, I just need help deciding if I should ask for her number, go to dinner and do fun stuff or should I back off completely. I also do respect boundries of her bf but she seems to be keen to the thought of us. I've also weighted the thought of other guys trying to get with her but I can only control me. Any answer will be greatly appreciated and thank you all for your help and I apologize for the length.