There have been some insightful earlier posts about Clive on mauriceclivealec which are very pertinent to your Ask: particularly THIS ONE, and also THIS POST which unpicks the ending. The social and historical context are really important, too: the intense socio-legal pressures on Clive, the further pressures of convention and class expectations (the Durhams are landowners Clive is the only son he must marry and produce heirs, etc), his limited options, and his internalised homophobia. Some of these focus in on Clive’s purpose within the novel (within Forster’s own purposes and perspective in writing it), and it can be useful to hold onto that (rather than feeling infuriated by Clive as if he was a real person). There are some good published analyses of Clive’s character ( here’s one I particularly like).
