Mum suddenly passed, am just not coping

I was 25 when my Dad passed suddenly, I was broken but had my Mum to take care of, she was then 65, we were really close, as the youngest as she got older I took care of her every need, as much as I could she was really quite fit for her age, a week before her death she went into hospital with an alleged urinary tract infection and pneumonia, her treatment in there was appalling and I have put in a formal complaint, plus requested her medical records, any way we got her home still on oxygen so my other sister, my husband and I took it in turns to stay 24/7. All that week she improved and by the Monday i stayed all day with her and night, she went off to bed, I stepped outside, I heard her call my name, going back in there she was trying to talk her eyes were closed, I reassured her and rang ambulance who made me do c p r on her, I begged them to let me stop as I felt her leave me, ultimately at 9.21 on 21 August my Mum was gone, and now I just don’t know what to do without her, my family were at her house the next day clearing stuff out so I had to be there too, her funeral was only last Monday, i am back at work, everyone keeps saying, be strong, being at work will help ( it doesn’t) I know grief does get easier after losing Dad, but despite having a husband I just don’t want to carry on, I miss her so much

My mother passed away suddenly and im devested as was very close to mum not sure how will cope

I know, it just all seems so pointless