Try eating a bit more. Since youv pretty much been starving yourself for three years its going to take a while but slowly work your way up to three solid decent sized meals a day. Take it slowly. I know its hard but to better your mental and physical helath you cant cut anymore (you’re not supposed to eat super super super small amounts of food to the point you get malnutritioned anyway) thats not how cutting works.3 years is really not good for you.(when you get back to a helathy state and want to compete in bodybuilding then maybe cut ( cut correctly) if you desire but not for like three years) Sugars ok and natural sugars like bananas and stuff is good for you, heck enjoy a donut ( unnatural sugars) every now and then if u like. Also your trainer is an idiot, if ur eating foods u dont want to eat and feeling miserable then stuff them. Eat dairy if you want to etc and get that passion for food back-but dont go over the top . Also try to eat in moderation.
Hope this article helps.