Crashed and Burned

An older man single and living alone was looking for a committed partner. He found a younger woman, and brought her to live with him. Passing shops, she asked for several pairs of high heels. He bought them. Requests involving more money followed like to buy nice clothes, pay installments on her car, and pay her back taxes. She promised to pay it back which she never did. She caroused the neighborhood (on a beach) and hooked up with a young dude. It was easy being seductive and pretty with big boobs. They ended up living together. He felt double crossed. His lingering thoughts were: will I ever learn?
He was mystified.