Gene has conflicting emotions about Finny having "practically saved his life" because it was Finny's fault he had "practically lost" it. Yet Gene continues to go to the nightly meetings and Jump from the tree without protest. Why do you think he does this

 This again has to with Gene's codependent rivalry with Finny. Gene resents and admires Finny at the same time. Gene wants Finny's validation while harboring resentment against him at the same time. In the end, Gene will not let disappoint Finny or let Finny completely outdo him.