Complex sentence: Malcolm too used to be a keen Young Conservative member before meeting Cressida, while canvassing, and being lured into a new world of progressive ideological debate and sex-he abandoned his dreams of becoming a future Tory Prime Minister, and grew a beard.
Split into simpler sentences: Malcolm too used to be a keen Young Conservative member before meeting Cressida, while canvassing. Lured by Cressida into a new world of progressive ideological debate and sex, Malcolm abandoned his dreams of becoming a future Tory Prime Minister, and grew a beard.