Welcome to Beyond Blue and well done for reaching out.
When I read that bit where you said "as I try to develop a healthy relationship with food, I have gained back all of the weight I have lost and more. I feel disgusted with myself ......" I thought 'yeah, I know right! I feel your pain.
I too have have had my own issues with food and radical changes in my weight for almost 30 years now. It started when I was about 21. At the end of July I will turn 50, and I KNOW that as I age, it gets harder and harder to lose the weight. I did manage to lose about 24 kilos two years ago, and went from a size 18-20, down to a 12-14. I am really happy with that, but I am also very aware that I have put back on 3 kilograms since lock-down and winter have hit. I do NOT want that 20+ kilos to find me again.
I too try to have a healthy relationship with food, but yes, it is difficult sometimes. Right now, for example, I am craving choc chip biscuits ...... but a few things are stopping me; one is that I don't actually have any here, two, I am already in my PJ's, three, it is COLD outside and I don't like the cold weather (I swear I should move up north!) and four, if I hold out, the urge will pass and I KNOW I will feel better about myself, knowing that I did not succumb to the craving. Plus, I have chewing gum. And that too serves a good purpose; it keeps my mouth busy and 'tricks' my brain. Plus, it actually makes my breath feel a bit better, and my teeth feel that tiny bit cleaner too ....... and who wants to spoil cleaner teeth with sugary snacks!
Also, if you were actually prescribed medication, but didn't take it, then that is perhaps just being your own worst enemy? My suggestion is to do what is best for you, and what the PROFESSIONALS suggest, and let your family members have their opinion, without having to adhere to it.
Anyway, I don't know if any of that helps. Just wanted to let you know you are not alone.
Take care, and feel free to keep coming back here for as much support and encouragement as you want and need. We are all here for you and with you.
Take care, I'll be thinking of you. xo