Depo Shot

I`am 19 years old and I have been on the shot now for almost 4 years in October of 2006, I have had only one main side affect and that is in my sex life with my partner of 4 years, It totally sucks because he thinks that something is wrong with me or I`am just not interested in him no more, but I tell him it is because of the shot. I would like to get off of the SHOT but, then again I haven`t had my period in almost 3 1/2 years, I do need to research more on what bad side affects from that alone are. Thanks Stephanie