Izuku Midoriya loved his mother. He loved her dearly! It's just that..
The secret behind his family situation gnaws at his insides.
His household is not healthy and he's well aware of it. His mother abuses him emotionally/mentally, sometimes physically of she's 'upset'. She manipulates him then acts as the victim for pure satisfaction. Not to mention the absence of a father figure in his life. Aizawa or All Might fill that hole sometimes. But only sometimes.
When Katsuki came over to his boyfriends house to stay over for dinner he couldn't help but notice the things Inko said. Inko was your mother but she would say things to fat shame izuku, when he was already really skinny. Or overall be toxic.
Katsuki knew Izuku wasn't like obsessing over food. Plus, Izuku was a pretty healthy person but inko made it sound like he ate 24/7. Izuku was very insecure about that so that didn't help at all— sometimes he'd go to the extreme length of starving himself for periods of times because he is manipulated into thinking he deserves to suffer.
During tonight's dinner,Inko was so sweet to Katsuki, while Izuku was just eating in silence.