I know that you are drinking lemonade for the sugar, but I would stop having it as the gas will bloat you. Have a sugary drink by all means but not a fizzy drink. A food supplement milkshake might be helpful.

My meds and depression make me lose my appetite, is your depression worsening now you are tapering off meds?

Mirtazepine is a useful anti-depressant for stimulating the appetite, my docs were really keen for me to give it a go when I wasn't eating but I couldn't take it for a different reason.