Both forms of diabetes are dangerous.
Type 1 diabetes is an autoimmune condition which causes our own body to attack the cells which produce insulin. It tends to appear at quite a young age but it is not unknown for it to develop quite late in life.
Type 2 diabetes tends to develop later in life as a result of our body resisting the action of insulin rather than the lack of it.
Treatment for type 1 will always require the administration of insulin. It may be required for type 2 cases but not always.
I suggest you explore this site
Blood Sugar 101 for a fuller understanding of these complex conditions.
I have moved your post to our forum for the friends and families of diabetics.