I get thinner when I'm eating!?

I AM SERIOUSLY GOING TO KILL MYSELF! I EAT A CRAP LOAD OF THINGS AND I KEEP GETTING THINNER EVERY DAY. I ALSO TAKE A WEIGHT GAINING SUPPLEMENT 2 TIMES A DAY WHICH CONTAINS 1250 CALORIES AND I GO TO THE GYM. I GET THINNER EVERY DAY!! WTF IS WRONG WITH ME!! I AM GOING CRAZY! WHAT DO I DO? I WENT TO SEVERAL NUTRITIONISTS AND THEY DIDNT HELP ME WORTH OF ****! THEY DONT UNDERSTAND ANYTHING.. I FOLLOW THE DIET AND NOTHING IS HAPPENING TO ME...