First blush, would recommend eating the Thrive Diet, it's mostly raw, it's also very balanced and addresses stress BIG TIME. Even if you can do it part of the way, check out Macca. Stress, even when you're doing all the right things, can just pack the fat away due to cortisol, so lowering that and eating clean, would be what I would address first. I'm really sorry you're going through this. Good thing you're staying far away from dairy/animal protein, it's cancer's best pal. Meditation and light yoga too and filling your heart with gratitude for the things that you do have, it's healing in a spiritual way and helpful for your physical body. These are my gut feelings about your situation.
Also, the earlier poster is right, when you're building muscle, the scale can stay still, but keep going. Your medication might be affecting it, you're right, but still, you're building muscle and increasing cardio vascular strength.
What I did to lose 50 lbs is this:
Every three hours eat 200-250 calories that are high in protein and low/slow in carbs. Peanut butter is my pal. Eat 5 x a day. (this calorie level is for my height and weight goals)
Exercise cardio 20 min EVERY DAY.
Strength 10-15 min a day, EVERY DAY. Heavy as I can handle without hurting myself.
Now my program is different to shed the last inches of fat and get ripped, I have a trainer now and her diet and exercise program is advanced and it's customized and I can't share it (plus it's very specific for each individual), but what I've outlined above will get you on the right track. I have a vegan trainer, google vegan personal trainer, she'd be the first link, I think. Online training. Yeah! Worth every penny!