ED treatment sucks. Too often professionals judge the severity of an eating disorder solely on weight and too frequently there isn't enough money/understanding to help people before it reaches a stage when your brain is too starved to really engage in therapy properly. I was 'lucky' to get some help long before hospitalisation would have been needed and even then, the second my BMI went above the anorexia criteria the community nurse discharged me, because clearly 0.1 BMI point makes all the difference between anorexia and fully recovered not needing any help *rolls eyes*
What mental health support do you have? I would use whatever support you do have to talk about food things and work out where these urges to restrict and lose weight are coming from and work on ways to challenge it. Talk to your partner, talk on here, see if there's any charity services in your area. But keep talking until you find someone who will listen and support you because tempting as it may seem, restricting and other eating disorder behaviours never lead anywhere good.
Do you have any ideas what is behind these cycles of restriction and over-eating?
I'm glad that your partner is insisting on sensible meals and snacks. It sounds like at the moment you don't have many reasons to resist the disordered thoughts so at least you've got your partner's support to nudge you towards recovery and hopefully you'll find many more reasons along the way. Are you involved in the food preparation at home very much? It's so silly but I can't tell you how much my relationship with food has improved now that I've got into cooking etc. I love trying out new recipes and ideas and eating stuff that I've made feels good. I don't even know what it is, maybe I enjoy the creativity, maybe it helps with feeling 'in control', but it's helped me enjoy food.
Sorry for this ramble, I hope some of it will be vaguely useful :)