I have type 2 and it's diet controlled, I have my annual medical plus an annual trip to Gatwick for an assessment with the CAA, no big dramas - its just the same as an ATPL requiring two medical assessments a year.
I concur with what has been posted, keeping weight down and moderate degree of fitness is essential along with being sensible about diet and lifstyle.
I'm an ATCO and as such the CAA were happy for me to take part inthe World Health Organisation trial for type 2 diabetics over 40 to take statins and blood pressure tablets.
I understand that pilots who are required to take the BP tablets may have restrictions placed upon them, in the vast majority of cases this is a two crew requirement.
As for taking tablets to control type 2, pilots and atcos alike take them but the CAA need to approve them before you undertake operational duties.
I have found that the CAA Medical Branch to be nothing less than outstanding with help, advice and encouragement, my GP's surgery have been able to liase with them with no problem and I couldn't have asked for a better service.