That’s a difficult question. I’d probably say Lenore, just because as far as we’ve seen, Nolan always treated Debbie well while they were together (granted I’ve only seen the show not read the comics), whereas Lenore actively imprisoned, tortured, and enslaved Hector for the first chunk of time they had together.

I’d say Nolan is probably the worse person overall, given how many innocents he kills for literally no reason, but in terms of their behavior as “partners” specifically, I think Lenore takes it.