Hi Scousemum and Shirleyknott and welcome to the forum.
Nothing but sympathy/empathy from me I'm afraid. My lad was almost 16 at diagnosis 3.5 years ago and with the greatest of respect to the mums of younger children, I think it's a whole different ball game being diagnosed in their teenage years when they have been afforded total independence and are already in that teenage mindset. They are given full control of their diabetes from day 1, yet are still so vulnerable and though could do with a lot of help, they also don't want it. To suddenly be held back by this and having to stop and think before going out with their mates is a big deal. After early anxiety over leaving home, our lad soon got into going out, like yours, refusing to take anything with him. He still does..........
We have been to hell and back with our son, and still don't have any answers. All it has served to do is destroy my relationship with my son. I love him so much, but he just resents, in fact I feel, hates me now. Yes, looking back, I suppose I drove him insane with my incessant "Have you tested?" "What is your BG level?" "Have you taken your insulin yet?" etc etc, but in my mind all I was doing was caring for him and wanting the best for him.
I understand his anger and resentment, and that he doesn't want to be different, but the sad fact is he is, and he has no choice but to accept it and get on with it. I do now leave him completely alone with it, just very occasionally it gets mentioned, but only on his terms. If I try and give ANY input I get shot down in flames, of course I know nothing! He goes weeks and weeks without testing, injecting is very hit and miss and complete guesswork, and I am amazed that so far he has managed to avoid an emergency admission with DKA, but I think that's more by luck than judgment. The mood swings are violent, you just don't know where you are from one minute to the next.
Oh, and there's another nasty thing on the horizon for you mums of younger teenagers, ALCOHOL! Hmmmm. Well there's another spanner to throw in the works. We're still working through that one!
Another thing I would add is do look after relationships with the rest of your family too. I put so much energy into worrying about my son that I lost sight of the others I care about so much too. It drove a massive wedge between all of us and we are only now getting back on track.
So sorry, no tips, just empathy. If you find any answers, please let me know!