You maybe able to get ESA and as MM says "as long as your GP supports you", as in .. supplying 'Fit notes'. It is either income or contribution based and you only get it for 365 days. You may well get help with your housing costs, but believe me it's a maze of barriers in the system when you try to break into it for the first time.
Having been in the same situation (still am) as yourself, I can assure you anyone who is British born and bred and has paid into this system all their working life, can expect nothing whatsoever in return if they happen to have been stupid enough to save a little and clear their mortgage.
My employers have recently taken me through the capability process and dismissed me on the grounds of capability. Strangely enough I have been capable of doing my job for 15 years, but after an incident at work I ended up having surgery and haven't been able to return to work since.
I can't give you any advice on benefits or support as I get nothing at all and have no income whatsoever .. but if I can give you one bit of advice I will ask you to keep a diary of every bit of info relating to the possibility of a capability process. Write down the time of every phone call, when it happened and who made it and what it was about. Keep any documents and letters, infact anything at all concerning your employment. Start now and dont say you will do it later !
Make sure you have someone with you if you have any meetings with your employer and take a notepad, infact take one each !
... and if it actually comes to a battle with your employer, do a bit of research on a 'Reasonable Adjustment Specialist' for representation.
Good luck .. !
ps .. GO AND GET THAT DIARY !