Funny how this all boils down to the story of how a man falls in love with his own wife.
When tennis pro Chris Wilton marries into a wealthy family, we are shown with paint-by-number illustrations, that he has become quickly and completely enamored of his life of luxury. Yet, he is so consumed with his passion for the enticing Nola Rice, that he would have given his wife's riches up entirely, had Nola been interested in a future with him, early in their liaison. She was not.
What unfolded was not just a man tiring (in classic literary fashion) of the mistress who had once enthralled him, but a husband becoming increasingly attached to the stability and unconditional love offered by his spouse. He started off taking it for granted and ultimately killed to keep it. This evolution is best evidenced in the way that Nola observes that the reason Chris can't impregnate his infertile wife is because he doesn't love her. When Mrs. Wilton finally conceives and gives birth it is a testament to how Wilton's lust for Nola gave way to the growing contentment he began to find in family life.
Interestingly, Wilton's wife and in-laws did not just shower him with money, but from the start they expressed support, friendship, concern and a blind trust that he hardly valued until he was at risk of losing it. Onscreen, Chris was never obviously aware of his growing need for family, but it can be heard in his reflexive denial when someone observes that he doesn't love his wife. It's not that he doesn't love her, he objects. Eventually, we see that he does, even if he never recognizes that.
As Chris changes, or because Chris changes, so does Nola. She goes from free-spirited and independent to clinging and insecure. Her world grows smaller, to the point where dreams are lost and Chris becomes her only focus. Yet, I don't think it's her degeneration that is driving Chris away, so much as it his distancing that's driving her to desperation. She tells him she's not beautiful, "what I am is sexy." Men may never have respected her, but they were always smitten. That's how she has come to define herself. When she loses her physical thrall over first her fiance and, then, Chris, she loses track of the only sense of power she ever possessed. The faster you feel something slipping through your fingers, the harder you try to hold onto it, hence Nola's tightening grip on Chris. Yet, I don't think his struggle to break the stranglehold would have been as fierce, but for the lure of the family life he had once eschewed.
When the movie began, we were never given Chris' background. We don't know where he came from, what he was escaping, but we were also given no reason to distrust him. When he told his new, rich girlfriend that he didn't want hand-outs, the only reason we thought he was lying is because, from Montgomery Cliff in the The Heiress onward, characters in movies who resemble Chris are always lying. But I think that in Match Point, Chris' lies -- like his crimes -- were always on the surface. We never saw him scheme to attain his expensive lifestyle. In fact, he seemed to drift towards it by default, because nothing more worthwhile beckoned. Things happened to him. He didn't make them happen. We only saw Chris take the initiative twice: (1) when he risked everything to pursue Nola, and (2) when he risked everything to kill her. Money wasn't his goal the first time, nor was it the second. Love was.