I am so sorry your both going through this, please let your daughter know those "friends" are not indicative of the future. Right now they are ****. I know because in the small town I grew up in and my group of "friends" were very cliquey. Caused a lot of social anxiety and depression. When I moved away for the big smoke and eventually Uni I was able to see how some respectful ans self responsible adults behaved... it had a massive effect on my mental health. The fact your daughter has Type1 as well means this stress is not helping.
I really hope the children's services are taking all this inboard. Has she been referred to CAMHS ? If not really push for it as they "can" be helpful. My 15yr old godson has been with them for the last 8months and it's been a huge relief to his Mum and family as he has needed the support. My memories of adolescence was full of highs and lows but nowhere near some of the pressures some of our teenagers have now. You can also access services as well as her Mum, honestly during this time, take what you can...
For you take some time, do something relaxing - regular walks, yoga (honestly it works), swimming. Anything to burn off those stress hormones.
Maybe your daughter could join you? She might not want the swimming due to scarring, but yoga is cool...
Some other Type1's should be along soon, if not parents.
HTH
GC