Threatening someone with violence is abuse (and is recognized as domestic violence), the way the Dursley's talk about Harry and his parents (calling them freaks etc.) is abuse, feeding him a tin of soup a day during the holidays (I think it was between first and second year) was abuse and, if the books had been more realistic, would have made Harry quite sick. Locking him up is abuse and, if there had been a fire, could have been deadly.
Whilst I enjoyed your story I am rather disturbed by your idea that there was no abuse.
Author's response
I did not say that there was no abuse; nevertheless, I appreciate your feedback.