Warren said it all.
Your mother is right about one thing when she said "not all diabetics have to focus on it the way you do." All diabetics should focus on the way you do, but they don't, and it will mean a lot of problems down the road for them.
It is far easier to watch your diet and and keep yourself healthy than to have to face "Heart Disease, Arteriorsclerosis, Liver damage, kidney failure, stroke, heart attack, PAD, retinopathy leading to blindness, neuropathy and possible gangreen leading to amputation" (quoted from Warren)
Why live a life that could be short and ugly, when you can live a nice, healthy long life by just watching what you eat and taking care of yourself.
Very destructive advice your Mom gave you.