Emperor never really cared for ML or his mother anyway.
We're not sure it really was the uncle. And the Emperor bears responsibility for being so narrow-minded and obvious in his dislike that he allowed someone to take advantage of it. I don't think NH would get to live a carefree life either. The Chu Clan would eliminate him since he's a potential threat to their own prince.
Song Yiting's love sub-plot doesn't really make sense. Could be written off as script diversion maybe or one of those bad Cdrama plotlines. But I don't find her love convincing.