how would you deal with a friend like this?

This is a very difficult situation. It sounds like she's hinting at you to pick between friendship with her or an intimate relationship with another person. I think she is like that because once you have a suitor, you won't spend as much time with her and you will drift apart as friends. One of my former friends was like that. She had a friend who had a boyfriend that she started arguments a lot with too. I think you just have to calmly tell her that her friendship with you is important, but that the other relationships in your life are important too. If she is truly your friend, she will understand.

it sounds like your friend is jealous .this is not the best behavior if she is your friend she would be happy for you and care about both of you.talk to her and let her know how you feel before it causes bigger problems.

communication is what all friends need to have. we do trust and love our friends but if commuication is absent, everything will fall off from its place. I think it would be best if you tell your friend how you really feel. The more you hide your feelings about her atittude would just ruin your friendship. Maybe she feels jealous thinking that you might forget her once you will have someone else. If she feels that way, assure her not by just words but also actions that no matter what she will always be your friend and you to her.