Antagonistic
Part of speech: adjective
Definition: Contending or acting against; as, antagonistic forces.
Example sentence: Most marriages are a mess, and the children get caught between two bitter, antagonistic parents. My parents stayed married for 27 unhappy years, till their kids were grown, and this was a catastrophe for us.
Alienating
Part of speech: verb
Definition: To convey or transfer to another, as title, property, or right; to part voluntarily with ownership of.