I think he loved her as a life companion. Not passionate love, but still love.
If you go back to ch 92 (and some talk btw Ellian and Edric around 88, I think). You will see that Ellian didn't hate humans. He thought they are stupid and like to betray, but he still did his works to manage them (as he was some kind of the lord at that era).
However, in ch 92, he felt betray due to the fact that humans belittled the 'love' (of Vampires) . Even we (their kind) love you (humans) this much, you throw it like a trash. He couldn't stand that.
Back to ch 75, Gunchan asked him that what he felt is 'regret' or 'betrayal'? I think that's the key of his hatred.
It did not beyond my expectation that he did not care much about his son. This person has never felt anything much from the first place. I think he just don't want her kid to follow his mother, to love humans too much and get hurt by that love.
So like, does the father love his vampire wife or not?
It feels odd when gunchan said he doesnt realy love his son. Basically he just hates human from the start n her death is the trigger?