what can we infer is the reason curleys wife married curley?

Pretty much her options were limited. Remaining single, for her, was out of the question. She felt trapped in the small town. Curley might have smiled once or twice plus he had money. She figured it was the best she could do.

Curley’s wife confides in Lennie that she could have been a famous movie star, but the world conspired against her and that’s why she’s ended in a barn with a dum-dum and a dead dog. We can infer she married Curly because she couldn't get what she wanted and because of that she was willing to settle for a man who's inherit a ranch and an easy life.