To save your life is why you MUST control your diabetes.
You need to retrain yourself to take your insulin. Surely you can programme a reminder into your mobile phone. ( even I, a granny, can do things like that.)
Alternatively, make yourself a "Supernanny" syle Daily schedule on a big bit of card and pin it up somewhere. Stick a star on when you remember something right Do it for a couple of weeks until it becomes routine. It may seem childish, but would set you a pattern.
Think of the little train in "Dumbo"
And say "Ican, Ican, Ican"
It's all a matter of routines.
E.g. get up, loo, wash/shower, brush teeth, check BG, take lantus, make breakfast, eat, take rapid,go out into the day, ready for whatever comes.