Are we a "couple" ???

Buddle_2

Hi. Just joined this site in the hope that someone out there who is cleverer than me will be able to shed some light for me.
Bought a house around 10 years ago with my then partner but we separated a few years later so I moved out but continued to keep up my half of the mortgage payments.
Due to circumstances, I had to return to the house as I basically had nowhere else to go, around 20 months ago
Discovered ex partner was now quite unwell & registered disabled with serious mental problems & on IS/IB SDP & DLA.
I moved back into house but live in totally separate areas - me upstairs & him downstairs We have separate bathroom, living & sleeping areas, and I even have a locked door to my part of the house. Works quite well.
Unfortunately I became unwell & was finally diagnosed last year & am unable to work. I now have to claim ESA, SDP & DLA.
As I said previously, we live totally separately.
Occasionally we assist each other when convenient - ie picking up prescriptions or getting a lift to doctors or hospital. Just general "neighbourly" stuff.
Yesterday a Customer Compliance Officer from DWP visited him & asked many questions on his living circumstances. EG do we live separately, who does his shopping, cooking etc? I don't do any of this (his sisters do) but I'm wondering that as sometimes I pick up his prescriptions or he gives me a lift to hospital etc if he is going that way, if maybe we would be considered by DWP as a couple and they would therefore insist we claim as such!!??
Apart from the odd favour as stated before, we don't live together or have any kind of "relations" any more (I seriously do not have the energy or inclination at present!)
I just wondered if anyone out there has a similar situation and if there is anything we should or shouldn't be doing in order to keep things straight with the DWP?
Many thanks in advance. :question:
PS sorry for the epic novel!!