My DM (64) has alcoholism and health problems for which she receives employment support allowance. She has received a fitness for work form from the DWP which needs to be completed and sent back. I have a strained relationship with her, mainly due to the alcohol abuse. I've tried for years, to my own detriment, to help and support her to no avail.
She's very close to her younger sister who has appointed herself my DMS next of kin. it's a very codependant relationship and her sister tries to overrule me when I try to intervene and support DM. I've had to detatch with love over the past year for my own sake as it takes it's toll and I have very young children.
I'm recovering from a period of poor health since having my youngest baby and am a lone parent to the baby and my older child who is disabled. My DP walked out on us a fortnight ago and my mental health is in tatters.
Aunt has lumbered me with the two large forms and wants me to fill them in for DM and send it off so she doesn't lose her benefits, but neither of them have given me the relevant information to write on the forms such as what medication she's on and for how long etc.
DM has poor literacy skills so can't do her own admin, and my aunt who happens to be perfectly lucid and intelligent says she can't do it because people don't understand her handwriting 
I don't know any of this because I've been pushed out, by aunt, who accompanies her to medical appointments.
I'm told not to get involved, but now there is admin to be done it apparently falls to me.
I've just sat down to try and complete the forms and obviously can't because I don't have the relevant information, not even her national insurance number. I don't know what medications she's on or for how long. I've been lumbered with forms I don't have the information to complete and it's stressing me out. I asked DM about her medications and she can't remember the proper names or exactly when they started.
AIBU to give the forms back and say I don't have the headspace for this. I've got enough going on myself.
Is this selfish?