Girl problems.......?

Here it is: About 3 moths ago, met this girl i really liked and we became friends and stuff. lets say her name is Alice. about a month ago, she confessed to me that she liked me, and i told her i liked her back. however, the next day, one of my friends asked her out and she said yes. i wasn't really hurt but a little jealous, but my friend didn't know that i liked "alice." lets say my friend who asked her out is named "Josh." so yesterday, tuesday, alice broke up with josh, and she told me that he just didn't show emotions or talked much. now my friends said he was sad but he doesn't look as if hes sad, so i don't know about that. so now, i want to ask "alice" out, but i don't know if i should because she was just in a relationship, and probably doesn't want to be bothered with a boyfriend, and also, it feels as if im stabbing my friend in the back if i go out with alice because he like her her. i don't know what i should do. also, "josh" is an Aquarius, "alice" is a taurus, so according to my other friend, tey wouldn't last long, and i just learned that im a virgo, so i dont know if we could last.