It's possible to like someone for traits that turn sour or get old faster than you thought.
I found my xh's outspokenness incredibly attractive at first - I thought he was honest, told it like it was, not hung up with taboos. I married him much too quickly. It became borne in on me that he was just unpleasantly rude and disliked most other people quite quickly after that.
I can imagine that LF was interested in current affairs, knowledgeable about acting (his family do about 10% of it after all), had a wonderful wider family, probably adored her, probably did some things that were a nice contrast with her exes, welcomed her getting pregnant. Haven't most of us been there? Whatever it is that makes a person vulnerable to online nonsense to that extent might not have been evident.