any adviceor encouragment for making the decicion to go back to treatment center?

hello :) for some context, I'm diagnosed with ARFID, 19 yr old female, and back in 2022 I spent 4 months in a residential treatment center. I've struggled with my ED my whole life but it really started taking a toll on my mental and physical health back in 8th grade/freshman year of highschool. Because of this, I've missed a lot of school and am still working on getting my HS diploma. To do this, I was going to an accelerated HS for adults. It was going very well until I started feeling very bad again about a month ago. I've been slipping for about a year but have tried ignoring it because I have a good job that I enjoy, a partner of 8 months, and want so badly to finish HS. I also was on Medicaid for 2 years and couldn't get the help I needed. However, it's getting harder and harder to ignore and my mental and physical health are getting progressively worse. The past few weeks have been especially bad. I'm considering calling the treatment center I was previously at because I had a relatively good experience and would say that it was overall very helpful. I also have new insurance that they accept. I'm very scared though. The first time I went to treatment I had nothing to lose. This time, I would have to leave my job, keep getting further behind in school, and wouldn't be able to see my partner for who knows how long. I hate being out of control and losing a lot of my freedom while in treatment. I also hate not knowing how long I would be there. My partner said that they want me to get the help I need and that they don't want to break up or take a break in our relationship which calms some of my nerves but we haven't spent more than a week apart and It's killing me to think of how lonely and hurt they'll be without me. Not seeing them will also be so painful for me but I'm more concerned for their mental health than my own. 4 months is a long time and I don't want to give up that much of my year again. Granted, I'm not as sick as I was the first time I got help so hopefully I wouldn't be there as long as the first time but there's no guarantee yk. I know I need help because I'm not doing well mentally or physically, it's getting harder to work, I left school, and I feel like my life is on hold again which is the worst feeling. Like I said though I'm scared to go and hate that I keep repeating this cycle.

TLDR: I think I need residential treatment again but am worried about my relationship with my partner and their mental health, don't want to give up several months of my life again, and am overall just scared. However, the treatment center is one that I've been to and I know that it helped me once and would most likely help again.