To be fair, they did have some comrade moments shown. As inside the lift on the way to reunite with Padme at the beginning of AOTC, they are having a good-natured talk about the past. Also in AOTC we have Anakin admitting to even Padme that he sees Obi-Wan as a wise and powerful teacher. And then in ROTS, Anakin saves Obi-Wan after he was put out by Dooku: if Anakin had truly hated him, I believe he would be the type to just leave Obi-Wan there and tell the Council he had died in an unfortunate accident. Later on in ROTS they have a similar talk about how many times Anakin has saved Obi-Wan.

Also notice in ROTS, and this is something few have drawn a connection on: Only when Obi-Wan says "You were my brother Anakin. I loved you." does Vader ignite from the heat. During all that time, they had been just as close to the lava as Vader was in that scene, and were unharmed. I see it as Obi-Wan's words touching Vader in a surprising way to the point that he lost concentration, and the "Force shield" against the heat of the lava broke. I think when Obi-Wan said that, Vader finally realized how much he had deserved his defeat. He had screwed everyone over, even his former brother/comrade-in-arms. Yet like that scene with Vader weeping, he doesn't believe there is any turning back.

Though Obi-Wan's memories of the person Anakin was were indeed overly romanticized, I do think Anakin did have respect, love, and admiration for Obi-Wan. It was his issue with pride that caused him to ignore it sometimes.