A Bucks County nurse who stole thousands of dollars from an infatuated, 71-year-old man with Alzheimer's disease was sentenced to prison this afternoon.

Donna Hammerstone, 46, sobbed and begged for mercy, while saying she didn't deserve it for "my horrible, horrible actions and greed."

Bucks County Court Judge C. Theodore Fritsch Jr., calling Hammerstone "an opportunist," gave her a three- to 23-month county prison sentence and ordered her to pay more than $15,000 in restitution.

Hammerstone pleaded guilty in October to accepting large cash gifts from the man and going on shopping sprees with his credit cards, even after realizing he was suffering from dementia. Police said she used the man's money to pay delinquent taxes, to purchase everything from jewelry and Victoria's Secret lingerie to a new heat pump for her home, and to lavish expensive Christmas gifts on her children.

When confronted by the man's daughter, and later by police, Hammerstone insisted the two were in a romantic relationship. Hammerstone is licensed as a registered nurse, but said she met the man socially and was not acting as his professional caretaker.

Hammerstone testified that the man had wanted to spend all of his $1.1 million estate before he died. She said he asked her weekly to marry him, and had insisted she accept his gifts.

"I felt completely helpless against this predator," the man's daughter testified in court today. Hammerstone, she said, had boasted that the man would do anything the nurse asked of him, calling him "my little puppet."

Prosecutors initially alleged that Hammerstone had stolen as much as $22,000 between September 2008 and January 2009, but agreed to let her pay a lesser amount to settle the matter.

Contact staff writer Larry King at 215-345-0446 or lking@phillynews.com.