I was diagnosed with diverticulitis and was started on flagyl and cipro (ciprofloxacin)? is that the usual therapy?

Yes but there's more: What you were prescribed is a very common form of treatment when diverticulitis is suspected or confirmed. The premise of rx is to kill the bacteria that are lodged in the affected diverticular pocket--in reducing the infection thus reduce the inflammation. Repeated bouts of diverticulitis, especially in the same location, warrant investigation & possibly surgery to remove the diseased colon area.

Yes, quite common: It sounds like you have uncomplicated diverticulitis, which is most often treated as outpatient with oral antibiotics, often Cipro (ciprofloxacin) and flagyl. Most people get better; most (about 65%) won't have any more episodes. For those who do have another episode, 99% are less serious than the first one. After the acute episode is over, make sure to drink enough water (64 oz/day) and add a fiber supplement.