Not sure if what I have to say will be accepted, but I need to say it anyway.
I have spent many, many years (I'm now 61) studying and researching near death experiences and life after death, and although I began reasonably sceptically, I can now say without ANY doubt ....
Markymark, your Mum KNOWS!
She knows you care about her, she knows you would have been there if you could have, and she hasn't left you. She's well and happy, and you can still talk to her - she hears you. She visits you in your dreams - which is often the only way those who have crossed to the other side of the veil can contact us - but most of the time our minds are too busy to listen. When we're asleep we're open to visits and chats from loved ones we can no longer see in the physical. Then we wake up and think it was just a dream.