Caring for disabled mum while in lockdown

Hi - I’m new here and looking for some advice.
I care for my mum who is in her 60s and has M.S (she is very physically disabled through this - pretty much bed bound) along with having early onset dementia. I ordinarily work full time and care for her 25+ hours a week too.
I have been told to work from home so I am basing myself during this time at my mums as it means I can keep a closer eye on her, as I would have to visit twice daily anyway (she has carers but there are many additional tasks they can’t do + staying away from her is simply not an option unless I actually fell ill myself- as she would simply would not cope) While she doesn’t come under the vulnerable list coronavirus wise (no respiratory issues, cancer treatments etc ) but my care is very much needed and she is considered very disabled and in need of lots of care.
Will I be safe to travel to hers in this lockdown situation? I’m prepared to carry paperwork with me in case I am questioned (her care plan listing my as part of her care, her PIP letter etc). I am not seeing anyone else as I live alone (except supermarket etc). If we go into total lockdown I will stay with her as probably easier but as it stands, I appreciate my evening time at home so I can relax for a few hours away from the stresses of caring for her (probably sounds a little mean but I need some time to unwind - if I’m at her house constantly I just can’t relax at all)

According to information available you would be able to travel

When are people allowed to leave their homes?
Mr Johnson said everybody should stay at home and would only be allowed to leave for specific reasons:

Shopping for “basic necessities”, as infrequently as possible. People should use delivery services, where they can
Medical reasons, to provide care, or to help a vulnerable person
Travelling to and from work, but only if it is “absolutely necessary”

Thank you for replying - I hope that stays the situation but who knows.