When peer groups avoid addressing disruptive behavior that's killing group dynamics

I'm part of a leadership cohort that meets monthly and there's one person who dominates every conversation and turns everything into a story about their company, and I can see other people checking out but nobody wants to address it directly because we're all supposed to be peers and supportive. We've lost three people from the group in the past six months and I think this is why but I don't know if I'm the right person to bring it up.