Take Beyoncé's advice and cater to your lady as a creative way to inspire enthusiasm for the game. Woo your lady into being an NBA fanatic with a team-inspired home cooked meal (Think Tex-Mex when the Spurs are on deck or Latin grub when Heat takes the court) and a well-stocked supply of her favorite cocktails.
Make the playoff game a party for two where your the host with the most (instead of you lazily screaming for sustenance from the couch, replace "HEY HUN, THE DORRITOS!" with "Darling, here's your freshly made Mofongo and a martini." Her ambivalence towards game night will change to enthusiasm faster than you can fetch her a fresh drink, believe that.