Cofee tends to make me vomit. It hasnt always, this started over the last 4 years. I imagine this is a sign of something. What could cause this?

Coffee vomiting. There are numerous potential explantations but one possibility is that caffeine causes the lower esophageal sphincter to relax and increase the potential for reflux which may trigger the urge to vomit. Discuss with your personal physician because endoscopy may be needed to assess the damage.
Maybe reflux. Interesting. It may be that the coffee is triggering a reflux of matter from the stomach up the esophagus-if you are having lots of heartburn and small volume vomiting episodes after you have coffee, this may be the case. It could be something else though, and you really should see your doctor to discuss this.