If my roommate and I were disagreeing about something, I would make sure that I talked to her about the issue face to face right away. I think that it is very important to address the problem before it has the opportunity to escalate. It is also helpful to refrain from being accusatory when talking to your roommate because if you go into the conversation blaming them for a lot of things, they will likely just respond with defensiveness or their own accusations (no progress will be made).
I would calmly and politely explain my feelings and then allow my roommate to do the same while remaining open minded and willing to compromise. Ultimately, if the disagreement was serious enough and we were unable to solve it or agree on a compromise, I would then go talk to my RA about the issue.
The best first step is to try to work the issue out yourselves but if you cannot, there are always resources available to help you.
~ Maggie Luongo