Lisa,
First of all, while I’m about to toss out what is basically medical advice, don’t have to tell you that you need to consider this carefully with your own health care providers. But I’ve been down the Dercum’s road for a while, and have read just about everything I can find on it and the related symptoms, etc.
It seems to me that your swelling would benefit more from compression therapy than from a surgical approach. Two half hour sessions of compression therapy could probably happen while you’re at work, on your meal breaks, or before and after your shifts. When I took the therapy at the hospital, I used a full-length boot, which compressed 7 chambers from toe to the top of my thigh. Now, at home, I have one that goes to just to the top of my knee. (I’m considering asking for a higher boot - I know my thighs are swelling now, although they weren’t really before.)
Compression therapy, when successful, is almost like magic! It can be painful, especially the first few sessions, when your legs are the puffiest. My doc actually prescribed Tylenol with Codeine for those times. Later on, it was only slightly painful. I started doing it again after having taken a break, and I’d forgotten how it would hurt those first few times. WOW! So don’t be shocked by that. It’s worth it though.
As for SSI, there have been several discussions here about that, and I’d refer you to those, just highlighting here a couple of points I was advised about before I applied.
I was diagnosed about 3 years before I was fired from my job for not keeping up- they actually cited my health issues as part of the problem. Six months later (during which I was able to collect unemployment benefits, and since we’d seen this coming, we were prepared for a reduction in income) I applied for Social Security. I emphasized the conditions which are really side effects, like lymphedema, fatigue, pain, inability to concentrate. I was specific about dates and locations and durations. Use your training and log everything. This will be very helpful when you apply. Both of my physicians (PCP and Dermatologist) were aware that I was applying and very supportive.
The day I got my last check from unemployment compensation, I was notified that within the next 10 days to 2 weeks, I’d receive my first monthly check for SS. Incredible.
My heart goes out to you. I have a friend who is also an RN and also has Dercum’s. She’s still working long shifts - for the same reasons you are, and to put three kids through college! - and I hurt for her when I know she’s worked two long shifts, back to back. It’s really too much for her.
She hasn’t joined this group yet, btw. She doesn’t really have the time for a group yet, using me to bounce things off of. The Lord led us to one another through a theology discussion group (on the 'Net) where I met her husband, a pastor. As we chatted, he realized his wife was going through (undiagnosed) what I was going through. He hooked us up and we became dear friends. Both our husands have been great about cooperating with meetings - I’ve been there, they’ve been here, we’ve met other places. We’ve got half a country between us but we’ve spent a lot of time together, and her kids are now part of my “nieces and nephew” group! 
She’s still homeschooling the youngest, and with the duties that go with being a pastoral family, other extended family responsibilities and working three part time jobs, this kind of group is in the future for her. Her name is Jane if any of you feel led to pray for her.
Sorry for the digression. I was trying to emphasize, Lisa, that I am aware of what your legs must feel like at the end of the day. and working in that kind of pain can be dangerous. It’s difficult to concentrate and hard to follow through, etc. Check into the compression therapy. What kind of pain meds are you using? Obviously narcotics are out. That’s why so many of us end up on Neurontin. (For me, a combo of Neurontin and Cymbalta has been very effective.)
I’ll sign off for now, as I’ve been rambling more than a bit.
Gentle hugs, and prayers, too.
me (aka Cindy) <
She’s still homeschooling the youngest, and with the duties that go with being a pastoral family, other extended family responsibilities and working three part time jobs, this kind of group is in the future for her. Her name is Jane if any of you feel led to pray for her.