Advise

First,why is she so annoyed with you over the game? Is it because you are spending time on the game when she is over or because you are spending alot of time on the game?

If she is upset because you play while she is there- it may be that she feels like she is visiting you and not getting the attention she feels she deserves and so she is upset about it- feeling neglected. If she feels like you are spending too much time on the game- she could be concerned (as a friend should be) IF you are spending a considerable amount of time on it. Put yourself in her shoes- hear what she is saying and WHY it bothers her. Then ask yourself if her concerns are legitimate. Reverse the situation and ask yourself how would you feel if the situation was reversed.

Now...with that being said... if she is making fun of you. This is different. If you enjoy something and she does not- That is ok and as a friend she should understand that. It is ok to be friends with someone who has different interests- however, if she is putting you down by calling you immature just because she doesn't like the game. She is actually the one who is being immature because she is making YOU feel bad just because you are into something different- and that is NOT cool. I am not sure what the situation is... but instead of arguing - ask her- why does it bother you that I play this game? If she says it is just because she doesn't like the game- tell her that you and she may not always like the same things, but that you can still be friends and that you do not like it when she says you are immature. Try getting to the root of whats bothering you both... tell each other how it makes each of you feel and work through it- if she is a true MATURE friend- she will do this and maybe things will get better,