I can really understand how your feeling op. You do feel really helpless, useless not being able to do things and I also got really down.
My break was a few years ago and I still am a little hesitant in certain weather or pavement's etc. I almost did a lot of damage to my foot due to some condition where my brain did not register my lower leg after my cast came off, it was consistently wet with cold sweat but was hot to touch as if it was dying, sorry cannot remember the medical term. My goodness the physios and other medical staff were excellent. It was a long recovery but I did recover all be it with a slightly larger ankle and many pairs of boots given away as my foot had changed shape.....but that had a silver lining as I had to buy new ones!
Joking aside the whole showering, washing hair and getting to the toilet was a pain, my poor husband trying to get me into a tiny shower cubicle on a plastic stool was quite painful (he has a bad back). I too felt guilty with him doing everything, but thank goodness he was around or I would of been really stuck. I could not even make a cup of coffee and carry it with the crutches, it was very frustrating. I was even making myself quite ill on an night time as I was scared to get up to go to the loo with crutches in case I fell over. I also had a injection every day for 48 days which my DH gave me after practicing on an orange.
You think its never going to end, but it does and you will recover of course some will recover quicker than others, your break sounds really bad and it will take time dont compare yourself to people who have broken ankles. Work with your physio do all you can to help yourself, I know others who gave up and are left still in pain. Oh and I found a limbo cover for my cast when washing handy.
When I went out eventually to the supermarket I used an electric scooter then borrowed one. It helped at first but I felt I was becoming to reliant on it so gave it back.
The first time I stood up on both my feet together and lifted my heels off the floor holding onto a chair I actually cried. The ancient Wii was a godsend to help with my balance as well. All small steps.
I will say many people just shrugged when I told them what happened, as if to say 'its only a broken ankle'..........
One bit of advice my fabulous physio said when I was discharged was when you go out, walk like a toddler as in with purpose and stride ahead...it helped.