I'm a 37m. i have a constant high bilirubin (~2.1mg/dl), and for several years, high mpv (~13.4fl), and low platelets(140-160k). what does this mean?

Probably nothing: I'm going to assume you are not taking any medications that will raise your bilirubin, and do not have a mild birth defect causing hemolysis. You probably have gilbert's non-disease. Your physician knows the workup, which is simple -- if you turn a bit more yellow if you skip a few meals, you're basically got the diagnosis. I would not be worried about the platelets, but monitor them.