I battle depression too and I completely understand how you're feeling.
Yes, you do have alot on your plate right now, there's no doubt about that. You feel like you're in this rut spinning your tires and you'll never get out of it. That what depression does to us.
One day you'll be looking back on this and you'll see that one by one, you've risen above each of these things that have you so down right now.
Being in pain, tho, really makes it hard to see any good in the future. (oh, how I know this!

)
Believe it or not, you DO have alot on your side. You've got a wonderful fiance and you both are young. Things have a way of working themselves out....you'll get all these things that you dream of. I'm believing right along with you that your SCS will bring you a means of pain control which will allow you to have a better quality of life, so you can enjoy things.
It IS hard getting on your feet at your age. I experienced it, I watched my daughter experience it.....yet it won't always be this way.
It won't.
Your friend you cares,

Rae