From the below scenario what legal defense does Samantha have?

Timothy and Samantha met several years ago. They had a very "casual" and "carefree" relationship for a couple of years. They would have secret encounters at bars, night clubs, and motels, while consuming large amounts of drugs and alcohol. Their "partying" relationship went on for almost five years.

Eventually, they both came to realize that they honestly loved one another, and decided to stop partying. They moved in together and settled down. As time went on, they fell deeply in love, and developed a very loving, trusting relationship.

After living together for one year, Samantha wanted to surprise Timothy with a romantic get-away. She purchased 20 ecstasy pills (a very popular "love" drug), and rented a night at a very romantic hotel on the beach. When Timothy learned of her plans, he became ecstatic!

They arrived at the hotel around 8 PM, and began to consume two pills per hour. By 1 AM they were both extremely high and enjoying each other's company. Around 1:30 AM, Samantha noticed that Timothy was coming in and out of consciousness. She tried yelling his name to keep him awake. However, he was completely unconscious by 2 AM. He then began to have seizures, and started to bleed out of his mouth.

Samantha became very nervous and did not know what to do. In a state of panic, she ran out of the hotel and went home. The following day, the sheriff questioned Samantha and informed her that Timothy had passed away. She was arrested and charged with manslaughter.