Well, you are running into a common problem with video sharing sites that many people don't really understand until they get the bill. I noticed that on your site, you have a video with a runtime of 16 minutes. That video is probably somewhere in the 50MB range. At the time I looked, 324 people had looked at it. Now, considering that most people who watch video sharing sites have broadband connections (we'll use a 3Mb connection average) the entire 50MB video would be downloaded to their computer in about 2 minutes. Now, for most people, they may watch a few minutes of it to see if they like it and, if they don't, they move on. If they do like it, they'll probably watch it to the end. However, considering what most people do when they are watching adult sites, chances are that they won't. So, in 2 minutes time, the entire video which is 50MB is downloaded to their computer. At 324 views, you are transferring 16.2GB just for that one video. With 300+ videos... you see my point.

At $120, you are definitely in the dedicated server price zone. For video sharing sites, I would recommend that you find one that offers you unmetered bandwidth. This way, you are not being charged overages due to bandwidth. A good resource to check is WebHostingTalk.com.