Hello, so sorry to hear about your mum.
I came here after losing my mum too in 2017. I think it is a terrible blow to lose your mum. There's no one else like your mum. It's a shock to lose anyone close, no matter how old they may be or what the circumstances are and it does knock the foundations out from under your feet and change your world, your future and indeed, changes you too forever. I know I will never be the person I was before I lost my mum anymore. My whole world changed in a moment and I changed too and both are taking very long time to get used to and adjust to. You just work at it from day to day and I mean 'work at it'. I found when I first lost mum, I became a wreck and struggled to do even simple things like getting up and dressed and often forgot to eat or drink enough, so that's the first thing you have to work at doing and if you even make a cup of tea for yourself, that is one little achievement! Finding your way forward into a future without your mum in it is a harder process and that too takes time and effort.
In the early days, I found little things helped, like having flowers around and walking in the park. The flowers lifted my spirits a bit and the park was a calming environment where I could sit and think and try to recover from the shock of it all. It is harder currently to do, but I found it helped enormously to get out of the house a couple of times a week, so I joined a class and that helped because it forced me to think about something else and to talk to new people for a while and that gave me a break from the relentless, overwhelming grief I was feeling. It was a much needed distraction and also made me engage with life again. It is so easy to let grief drag you down and if it gets a hold on you, it is hard to escape from its clutches. I reached a point about six months after mum died, where I was in such a state, I knew I had to do something to help myself of go into depression, so I made a plan for the future, both to help shape a new future for myself and to help me recover on a personal basis and the class was a major part of that. You can do on-line things, so that might be helpful, but also face-time calls with friends also help and even texting and chatting that way.
You need to make an effort not to just sit with your grief on your own, so I do encourage you to talk to someone about it, even if it is just us. The other thing that helped me quite a lot was to write about how I felt about what happened to mum and to write about what happened when I lost her with all the disappointments and upset and pain included in that account. I then kept a diary writing about how I was feeling every day and still do. It helped somehow to express all of this by writing about it and relieved some of the pent up pressure that grief puts onto you.
It takes a long time to come to terms with a close loss and there will be good and bad days and then good and bad weeks as time goes on, but I cannot subscribe to the popular expectation that you ever 'get over it'. You learn to live with it, but don't really get over it. The pain of that loss becomes a part of you and is never really gone, but it does improve and, over time, the painful memory of those last days fade and some of the better memories resurface and your mum will never really be gone from you. She made you who you are in part and you will always be able to hear her voice in your head when you are wondering what advice she may give you when you need it, so you will be carrying her with you in your heart and mind for the rest of your life. She is part of you, so how can she ever really be gone from you?
Be patient with yourself and make an effort to take care of yourself, but just take it one day at a time. It's the hardest thing you will ever go through and it's a struggle to make it from one day to the next, but there is light at the end of the tunnel. Others here describe it at as a rollercoaster ride and it can be like that, but it does get very slowly better as acceptance comes and the shock subsides.
You will and have clearly already found that the help you might expect from others, does not necessarily come. I find that unless someone has experienced loss themselves, they just don't understand how hard it hits you and have no concept of how it feels or how very hard it is to recover from that. People who have no experience of loss are the ones who expect you to be able to 'get over it' and somehow go back to being who you were before it happened and for life to return to being what it was before you lost that person, because for them, it was sad, but was no more than that for them. For you, it is so much more and so much harder and they will not understand that, but everyone here does and we are here to help you through this for as long as you need us. Talk to us; request counselling from your GP if you think that might help; talk to your family and your friends, if you have people around you can talk to about it, but do talk and it will help, even if you just talk by writing it down, or perhaps talk to your mum herself - some people like to write how they feel in the form of a letter to the person they have lost.
I hope some of this helps you. Wishing you well and sending strength and empathy.