Ari, inpatient/residential treatment can be really helpful. It's important to be clear about its benefits, why you might choose to go, and what you can reasonably expect to get out of going.
I've seen families be disappointed by the results of inpatient treatment, because they inadvertently had expectations that weren't grounded in what was reasonable.
Inpatient treatment is terrific at providing tons of structure (which can help a person significantly change behaviors- sometimes ED behaviors are just too difficult too change when someone is going around in his/her regular life), support, sense of community, stability- and these are just a few things that I'm mentioning. I'm sure you and your therapist will continue to talk about what decision you'll want to make.
What I wanted to say to you is that inpatient treatment needs to be looked at as one point on the journey of recovery. It's not the end all be all of your treatment (although it sure can be an important, even crucial in some cases part of it). You'll likely still see your therapist that you see now once you finish a program- you'll just be farther along in your work.
If you decide to go, you certainly don't need to know exactly "how it will turn out" or how you'll be feeling afterward. Try not to put that kind of pressure on yourself. If you go, you'll go and you'll work hard. And then you'll continue onward as you come out of the program. That's kind of the end of the story (and it can be a very good story).
So many times I've seen people feel like they somehow have to be "cured" when they come out of a program- or that they have to "do the program perfectly," and if they don't they will have failed. As far as I'm concerned, if someone genuinely tries and works with an open mind and heart when she is in a program, it's considered a success- I don't know what "doing a program perfectly" would even be! There isn't a way for it to be done perfectly.
As you proceed with your thoughts about what to do next, I hope you can allow yourself to look at where you are now, what you truly need and want, and make a reasoned decision about what to do next. In any case, nothing is written in stone. I do advise people to not commit to inpatient treatment unless they really feel ready to go- but at the same time, if you go and it wasn't the correct decision for you, you are certainly allowed to change your mind (this process isn't about being perfect, remember!!!).
You don't have anything to lose here. Just take one step at a time, try to be honest with yourself, and let those you trust help you figure out what you want to do next.
In addition to your therapist and anyone else you have to help you with this, please feel free to use me as a resource. In addition to my private practice, I've worked in and directed programs, and I routinely send clients to inpatient/residential programs all over the country.
Good luck with your process regarding this. As long as you stay honest with yourself, you'll come to the best decision you possibly can for this point in your life.