Hi Caryolyn, a 5 month flare is certainly possible. From the postings on this board it seems like "flares" can really be from days long to months - it's very individual. My current flare is going on 6 months long. It seems to go through stages where I appear to be getting better for a week or two and then suddenly relapse backwards. It's definitely frustrating. The surgery question is a good one. It certainly can cause a flare up for some and did for me. Personnelly I need to have a follow-up surgery but, we are pushing it out until I stablize.
Hope that helps answer your question.