Perhaps you could, but I still think it likelier that he was trying to preserve her as an asset. Don’t forget, Phillip was pretty broken-up when Analise was killed. And he did tell Martha, “I’ll protect you.” Sure, he could have been blowing smoke, but I don’t think so.
Elizabeth is a lot more able to detach (almost to the point of borderline sociopath territory). She’ll sleep with a guy one minute and slice his throat the next.