I am 27 and have been type 1 diabetic for almost 2 years. I have never had weight problems and there was no family history of diabetes so it came as a major shock like it was for you.
At first it is frightening and stressful and may take a while to get your head around but things get better. You need to have a sensible diet but there is nothing you can't have - it's all about balance. You will get used to injections and it will be come a routine rather than ordeal. You will get on top of it and while you will never have perfect blood sugar control you will do the best you can either with the use of 2 or 4 injections a day.
You can get depressed and let diabetes control you but the key is to be positive and control it the best you can. You may also hear scare stories of bad things that can happen but if you can keep good control of your blood sugar levels then there is no reason why anything bad should happen to you.
There are alot worse things than diabetes out there and treatment is readily available. Keep positive and you'l do fine I am sure.