Mum passed away more than a year ago and I don’t know how I’ll ever feel happy again

My mum passed away on the 3rd of February last year, after 18 months of brutal illness with ALS. She was 57, I was 28 and my sister was 30. I felt like I was grieving as soon as we found out that’s what she had. There was no cure, nothing but worse to come. And the worst did come and it was fucking horrible. I think I’ve been in shock for the past year. I would cry and be sad but I felt so numb, and now I just feel so heavy, and so dark. It’s Mother’s Day in Australia on Sunday so I guess that’s making things feel even worse, but I don’t know how I will ever get out of this hole. My dad and sister live together in the same house, it’s exactly the same as when she was here. All her things are left as they were. Our lives are just so sad, and I keep trying to find a way out but I can’t seem to find one. I feel like there is no hope, and I can’t find a way to look forward to my life ahead. I have a beautiful boyfriend and future together with him, but I just can’t see a future for myself. I can’t picture it. I think about her and miss her constantly, but as time has gone on I don’t feel like I’m getting better I just feel like she’s further away. I don’t know how to get out of this hole.