id get her to a gp and get mental health plan in place.
this will then entitle her to discounted if not free social work care and psychiatry.

When she is on this she will be able to apply for a disability pension once she has a diagnosis.
she will not be eligible until she has a diagnosis.

you will also need to see the GP without her, if you want to be the support person and find out what you need to do to make sure she is coping and your coping as it is a very stressful job being a carer.
from previous posts i don't feel you want this role.
and there is nothing wrong with that hun, nothing at all its a lot to ask of anyone and especially when you have your own family to care for.

But first call is get her to a GP for MHP.

good luck and its a hard time for anyone..