I have a history of eating disorders as well, and recently went on anti-depressants and have experienced weight fluctuations so I understand what you are going through. It can be very triggering.
Pease do not restrict your calorie intake, especially to such a low number. Restricting your calories to below 1200-1600 is extremely unhealthy and will actually negativity affect your metabolism such that you keep having to eat less and less to maintain the same weight. It’s a vicious cycle.
More importantly - it is not a solution to your problems. Your substance addiction(s) and your eating disorder are responses to larger issues. They are both methods of “checking out”. Whether it’s drinking to oblivion, or obsessively counting calories - they are both ways to distract your mind from the deeper psychological factors at hand. They are both ways of making yourself disappear.
I second the suggestion that you seek out specialized therapy for eating disorders. You may even need a daily inpatient or outpatient program to get you started. I know that sounds scary, but it is absolutely worth it.
You are worthy of love and respect no matter what shape your body is. It is okay to take up space in this world. You do not have to listen to the fucked up messages our culture sends you about how one is “supposed” to look. I know it may seem like a fact that thin is beautiful and fat is not - but it’s not true, it’s purely cultural conditioning. Learn to question the culture and ask who is benefitting from these ideas - because it’s not you. It’s magazines, diet companies, and people you want to objectify you.
Did you know that in parts of Mauritania and Niger, the fatter a woman is the more she is considered desirable? It is considered a sign of beauty and wealth. Consequently, many women force-feed themselves to the point of illness - or even death. It seems crazy from our perspective, but is it any crazier that people getting sick or even dying from trying to be thin?
On a practical level. Throw out your damn scale. Or take a sledgehammer to it if you feel the symbolism of the act would be beneficial. Get rid of, or put away, clothes that make you feel like you are the wrong size. Treat yourself to something beautiful in a larger size if financially possible.
Feel free to PM me if you would like my contact info, I’m happy to talk about this more if you want to!