You know how T'Pol was a stubborn pain in the butt and did NOT take E2 T'Pol's advice about letting Trip in? About following her heart? Well imagine if she had taken that advice, she and Trip might not have even been on board the Enterprise. They might have been off somewhere, with a family, or on another ship entirely. Perhaps they would have worked together on earth to further Vulcan Human relations or perhaps they might have been on Vulcan so that T'Pol could have a child. There are very good reasons they might have made a new life for themselves if T'Pol had followed her heart and Trip might never have died.