I think Madeleine is saying, that what Travis was saying was indeed "not nice" (completely subjective imo) but that what he was saying was in reality the truth. Sometimes, you have to dealwithpepure evil with evil. He was done with her, she wasn't getting any of his other prior attempts at letting her down gently. So he took this approach, unfortunately for Travis this is what likely was the ignition to his murder and his last few conversation with her were not so nice, they weren't intended to be. That's where the relationship had evolved to