How do I know if a girl is romantically interested or just wants to be friends?

Anonymous
So I've been burned enough times because I just can't seem to tell the difference between a girl who wants to date me or wants to be friends.

I have this friend whom I've known for about 6 months know. About 4 months ago I broke things off with one of her works friends who I was sorta seeing (for only a month). I'll spare you the details but it was kinda dramatic. Anyway, this friend of mine was really supportive and it made me realize I was going after the wrong person. Over the past few months I've really started to get strong feelings for this friend of mine.

I've started flirting with her and she seems to flirt back but like I said before I can never tell if a girl is flirting because she is actually interested or if she just seems me as a close friend. She does things like briefly lay her head on my shoulder (done this about 10 times), playfully punches my arm, playfully teases me and calls me goofy names, texts me just about every day to ask my plans for the night or ask what I did the previous day, IM's me on FB if we're both on, vents to me about her work problems and stuff, apologizes to me when she thinks she was acting lame, and even once I caught her looking at me from the side of her eye while drinking her drink and she started to giggle when I smiled back and asked what she was staring at, and she doesn't seem to pull away if I subtly touch my arm or leg to hers like if we're sitting next to each other or rub her shoulders/back. I know your probably thinking that I'm dumb because she is given me so many signs, but I guess I'm more hesitant because I have had a history of female friends who would flirt like crazy with me (cuddle, text me all the time, go on 1v1 dates, etc.) and when I would make a move and get friend zoned and look like a fool. Plus I don't want to cause drama by making a move and being rejected since she is part of my group of friends. If she wasn't in my group of friends this wouldn't be a issue because I could just walk away if I got rejected, no harm no foul.

So I guess this question is sort of twofold. First of all do you think this girl is romantically interested in me, or does she just see me as a close friend whom she is comfortable with? And what do girls do differently when they have a romantic interest in a guy as opposed to wanting to be just friends?
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+1 y
So she's been playing me all along. Go figure. Story of my life I guess. The real doozy is she is not only doing this to me, but to one of my good friends, and the guy she really wants doesn't give her the time of day. Karma's a bitch. Needless to say I won't be hanging with her nearly as much because I hate being played more than anything. Thanks everyone for you advice.
How do I know if a girl is romantically interested or just wants to be friends?
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