He might have been mad at Eb but ultimately he eventually accepted him as a good man still, despite his reservations. He didn't realise that Eb wasn't merely morally grey, but also an incredibly savage and violent man at times. He hadn't really seen that side of him. Harry realised that is how he looks sometimes from the outside too. But it surprised him that Eb didn't have excellent self-control, because he assumed that Eb did (partially because he was meant to be older and wiser, and partially because he expected a Senior Council wizard and Blackstaff to handle his emotions better). But Ebeneezer is only a man, only human. Harry just keeps learning the hard way.
However he did see it coming, that is why he had Molly make the ring for him. Harry knew, as strong as he is, even with the Winter Knight's mantle, he was no match for Eb pound for pound. He also knew that where Eb was at emotionally, he couldn't be reasoned with safely. And he was right, if it had been him instead of a double of him, he'd be dead. After the fact, to Eb's shock and horror he realized he was out of control, not a good place for the Blackstaff. It hurt, but Harry knew how it would go down, so he had his double fight Eb. There was no time for anything else, Eb couldn't be reasoned with, and yes, Harry still loves him, but Harry also loves Thomas, and meantime the world is going to hell in a hand basket. As Warden of Demonreach, Harry was in a position to at least keep Thomas safe for the moment and at the same time satisfy diplomatic and justice demands. Eb had reached a point where there was no explaining that to him. Which brings us back to family dynamics, Harry and Eb cannot communicate here because both had been withholding the truth from one another for too many years.
Harry loves Thomas, he knows he is a vampire, but he is also his brother. Eb hates vampires, perhaps with good reason, so he thinks a good vampire is a dead vampire. Because he doesn't know the truth, he has all kinds of horrible fantasies as to why Harry wants to save Thomas. When he learns the truth, he cannot handle the shock of any of it. Harry doesn't know the truth as to why his grandfather hates all vampires so telling him who Thomas really is didn't go down so well. Throw in
Eb revealing that he thought it best to ignore both him and his mother until their talents revealed themselves.. No, both are too pissed to listen to reason.
I entirely disagree that Eb hasn't earned the right to give advice. He did LONG before Harry knew about their family relationship. He was Harry's mentor and teacher, he more than earned the right. Not to mention, Harry seems to be fine with this by and large, unless of course it goes against what Harry wants. Harry is only human himself. But Harry is learning when to heed advice and when not to. He has mostly improved a lot in this. But he still has some way to go.
Family dynamics, they do not follow logic my friend. Eb was a revered mentor and teacher who hid the truth about who he really was from Harry. Now he may have had good reasons for that, but it never turns out well when the truth is hidden. It is resented, the reaction is pure emotion, there is no way Harry is going to listen to anything Eb has to say. Harry knows what he has suffered for years because he thought he was an orphan alone in this world.. Sorry but the answer Eb gave for letting that happen isn't going to cut it. Now Harry isn't so pig headed or stupid not to realize that he has to work with Eb in this crisis, he knows he does. However if Eb survives this battle he has a lot of work to do to repair what he fucked up with his daughter and her son. Nor is Harry going to take advice on how to protect his brother or raise his daughter from a man who seemingly didn't give a damn about him or his mother, until Eb can explain it. That hasn't happened yet.
respect you think Eb is going about convincing Harry the wrong way. That's a fair call. But Harry is notoriously stubborn and difficult to convince. And you might remember that one of Harry's main regrets in Christmas Eve was how arrogant he is during Peace Talks and Battle Ground (and how much it cost). I think Eb is just probably the wrong person to convince Harry altogether. Eb would probably better getting someone else to make his argument for him. Like Murphy or Michael. Assuming they agreed.
First of all we don't know yet, what Harry's regrets are at Christmas. I suspect it has more to do with deploying a weapon of mass destruction because that is the only way the Titian can be stopped and the city saved. However that comes at a horrible price, a lot of innocents will could die in the process. Now Truman claimed he never lost a minute of sleep over giving the orders to drop the Bomb, because in the long run it saved more lives than it took. But Harry isn't Truman, deciding life and death on that kind of scale does take a lot of arrogance. The point you are missing I think, is in the end it still comes down to family dynamics.. Oh Eb might be able to logically convince Harry that was the right decision on mass destruction, but Eb the grandfather has a long way to go and a lot of explaining to do before Harry accepts anything he has to say on how to raise his daughter or how to treat his brother.
Oh for the record, I don't think Murphy can help Harry on matters of mass destruction.. It felt good to be hugging her for sure, but it was clear that she had no grasp on what really was at stake. But then again, perhaps it is too much for a mere vanilla human to get her head around.