Hi Flea - and welcome :)
I completely understand how you feel. In my opinion, depression encompasses everything you know - it makes even the tiniest thing that you used to do every day turn into something huge and unmountable! I know I personally found my 'comfort zone' getting smaller and smaller until at my lowest there were three people I could talk to and literally one room in my house that I felt safe in! And you begin to rely on those 'comfort zones' and as you do start on the road to recovery you find that the 'comfort zones' start to get bigger as you start to let yourself become accustomed to 'new' things again - I still operate within one and I know what I am comfortable doing and what will send me straight back down and although those things - even to me seem silly (let alone someone who has never experienced depression) I know I cannot push it - I can't LET myself get tired, I have to just see friends in smaller groups and for short amounts of time, I cannot go out on my own yet.... it all takes time, depression is not something that you wake up one day and its completely gone. But you have to just be thankful for the small things - for example my boyfriend congratulates me if I manage to almost finish my dinner!! (I've been borderline anorexic for the last year) and I know that one day, I may manage to eat three small meals a day and the next... I might survive on milk and a couple of crackers! I know its not healthy, but its progress compared to what I was like three months ago!
And yes, the thought that one day I will 'be better' does absolutely terrify me at times - when you are at your lowest everyone is supporting you, nothing seems to be too much trouble for them and sometimes I wonder how I am going to cope when I haven't got that support network around me. But I have to remind myself - they are not going anywhere! My mum, dad, boyfriend, friends - even my support workers KNOW what to look out for. The people closest to me have also lived through this for the past year and they do not want to see me on a downwards spiral again so even when I am 'better' I know that I am fortunate enough to have people other than myself looking out for the signs that things aren't going that well. But also - please remember, you are still 'in recovery' when you are back to 'normal' then being well won't seem as scary because you will be there! And it may be in a few weeks, it may take months or even years! But it will happen one day - and in the meantime please just take comfort in the little things and listen to what your body is trying to tell you.
I hope it all goes well for you, please do keep me informed.