I never liked him. At times during S1-S4 I loved to hate him, but the most time I just really hated this character and I didn't love it, if you know what I mean, haha!
In season 5,6,7 and 8 he started to bother me more and more. I get he wanted to apologize and that he was searching for a way he could do that, and be forgiven ; but it's like he did nothing else than that. Like a puppy, asking everyone to forgive him in whichever way he could.
That's why I was so surprised that I actually felt for him, when he died. At that time...I sort of forgave him. I can never forget what he did ( and I am not even talking about Keith...but the kind of ''dad'' he was to Nathan and especially Lucas + how he treated Karen/Debb ), but I learned to live with it around 9x11. His scenes with Haley/Jamie and Lydia were just hearthbreaking. May the best scene out of the whole show. And his exit with Nathan and Keith was perfectly done. He got redemption at some level.