How can I know if my friend (girl) likes me?

Hi I'm a girl and I'm 25 years old. I have a friend (girl) who is also my neighbor. Her son and my eldest daughter are the same age. Before, I didn't talked to her a lot but now we became the closest friends ever. I'm spending my free time with her and she's doing the same. We're always together, we shop, do the groceries, take the kids out etc... There's no day I don't hear something from her. She writes me messages & calls me atleast once a day. Her messages are so sweet, she even wrote "I LOVE YOU" more than once. I don't know if I should take that serious or not. She's very thoughtful, she cares about me and she's even acting sometimes like she's my lover. She gets upset/sad if we don't see each other or if I don't reply her messages. Sometimes she gets really jealous if I'm talking and laughing with my other friends. I even notice if she's looking at me from far. I don't really know what's going on. But what I know is that we have this special connection or relationship that only both of us can understand. But what it is, if it's a flirt or even love or just a harmless friendship, I can't really tell. I don't know if she has feelings for me but I think I mean something to her. I mean I got friends I know for ten years but they don't do stuff like what she's doing. I really want to ask her if she likes me but I'm scared. I don't know how she would react. I don't want to risk our friendship coz I really like her and I don't want to lose her as a friend. What if if she says " No, I'm not a lesbian." I don't wanna be embarass.

One good clue: If she has a daughter she apparently had a relationship with a male at one time. Does she still have a male in her life? If so, does she seem happy with the relationship?

The best way to understand how someone feels about sensitive issues is to bring up the subject a general way. Find a movie about two women in a relationship, watch it with her and listen to her opinions. You'll have your answer before you get to the end.