The list of Groups seems to sort in a random order (possibly) order of creation. We can sort the list manually into alphabetical order, but it doesn't keep this setting and we have to keep re-sortin...
I agree, from what I can tell, is that the sort is sorting the SHARED groups first, then your personal groups next, this is not ideal, at least not in my experience, as I use items in my personal group way more than I used the ones in SHARED Groups.