Narcissists usually have a basis for their circus mirror view of themselves. If his mother is the one who always told him he was perfect, then when that view is challenged, he will need to reaffirm it or else re-evaluate his self image (which most adults are almost incapable of.) Therefore, when you say he's abusive, he needs to call Mom to make sure it isn't true. This is probably a re-occuring theme in his life, so get used to it if you're going to be with him.
abusive or insulting online is called
abusive
The whole question 'to get even', 'called me a thief' is a sign that it's an overall poor relationship. I wouldn't say abusive based on one comment, I would say that the whole relationship is in doubt.
A narcissist!
It might be called a rant.
A person who loves challenges is called a narcissist. A narcissist values themselves a lot and is very selfish.
Egotistical Narcissist
In "A Child Called It," the father did not intervene to protect his son due to his own issues, such as alcoholism and his own abusive tendencies. He was not emotionally or mentally equipped to stand up to the mother and protect the child. Additionally, he may have been influenced by fear of the mother's wrath or manipulation.
(abusive answer deleted)
This is called homophobia.
Abusive behavior that specifically targets gay people is called homophobia.
A narcissist and more extreme would be psychopath