He was consistently testing her boundaries, trying to find some way to get her to sacrifice her values in an attempt to please him; her way that people will take advantage of poor boundaries.
Anyone who remembers high-school will likely recall that one toxic friend who would steam-roll over others in order to get his or her way; anyone who resisted was subject to inordinate amounts of social pressure – trying to utilize the social contract to push others into doing what he or she wanted.
After the honeymoon period, where I was just astounded that I was having sex, our relationship became a matter of constant fighting, jealousy, guilt trips and having to justify myself on an almost daily basis.
Almost every fight we ever had would escalate from disagreeing over what to rent at Blockbuster to threats of breaking up with me… I allowed her walk all over me because I was willing to put up with this.
Many people will cheerfully take advantage of those with weak boundaries; they look for people who are willing to put the well-being of others above and beyond their own in an effort to please others and make them like them.
One of the most common signs of a predatory, abusive personality is the testing of boundaries: trying to push someone further and further out of their comfort zone, using a cycle of rewards and punishments in order to manipulate someone into being willing to knuckle under.