I agree with most of what others have said here because I too suffer from RSD/CRPS.
I Haven't posted here for a long time & your post brought me back because I struggle with dating now, too. Mostly because I am nervous about how people will understand, having had many close friends & relatives that don't get it it because it is, largely, a disability you cannot see most of the time. We become really good at faking feeling good to make others comfortable but we can only do that on days when it isn't too bad & for short periods of time. I'm nearing my 8th year of having this & still encounter it with people. I often push myself past my physical limits to avoid letting or what I perceive as letting others down, letting them see how I feel because I don't want sympathy & also know some people just won't stick around if you can't do what they want to do, which may be something as simple as standing in a crowded social situation when chairs aren't available to a simple walk. You find out who your true friends are and aren't, but regardless, a lot of people have difficulty being around people with any type of chronic pain or disease.

So, even though I want to begin dating again, I always worry about finding someone that will understand what my life is like & be ok with the fact that there are days when I will have to cancel at the last minute because flares can strike at anytime for no reason. We have no control over it, which is a hard thing for us to cope with. Add feeling like you are letting someone down because you have to cancel plans at the last minute or have a hard time planning anything because you don't know how you are going to feel that day & it adds a lot of pressure.

I applaud you & suggest you just do your research (rsds.org is the best place to get the info you need to understand & support her) so you can grasp what life is like for her, but also don't treat her like she is RSD. It is just part of her life now, likely forever, but we are not defined by it. It is a hard task ourselves just to learn to accept our new limitations and lives because for all of us, it changed our entire lives in an instant & in our mind, we are still the person we were before it struck, so there is a disconnect between what we want, think, etc and what we can actually do. We know if we push ourselves we will likely pay for it for days or weeks afterwards. Having someone who accepts that, expects that & doesn't constantly remind us of it but just lets us be & do what we need to do for our mind & then recover for our bodies is pretty incredible & rare.
Once she learns you can handle her bad days in whatever way she prefers (I prefer to be left alone to try & deal with it, not being asked constantly what you can do or worse, suggesting trying things....believe me, we have tried everything) and it doesn't scare you away, you can be flexible, etc., she will learn she can trust you & will probably open up more. Be aware & pay attention to her behavior & moods & you quickly learn the difference between her bad days & more functional days. On days when she feels good, she will probably want to push herself because you want to take advantage of every lucky minute we get, even though we know we will probably pay for it later, let her do it. She knows her body & what to expect by now. Hanging on to any control and independence we still have & can get it very important to us. A good sense of humor is a key characteristic I look for, because if you can find a way to laugh even when you are miserable, it makes life more bearable.

Best of luck yo you,
Darla