No, she isn't, she wanTed to BE Trixie, not fuck her. It's because Timmy liked Trixie and she like Timmy. I mean the exact episode this is from shows this, not to mention all the oother episodes showing she liked Timmy.
Also why did Timmy have 2 stalkers, even Trixie was shown liking Timmy when they were alone not just when he was the last boy on earth but after he gave that speech but with the comic thing and loveletter in op's pic, not to mention Vikky falling in love with adult Timmy.
What kind of shit was Butch up to?