Richard Honaker prescribes Chantix to patients and while he urges caution with the drug, he believes the possible risks may still be worth the benefit.
"More patients by far are able to quit smoking with this drug than anything else we have," Honaker said.
A 28-year-old stayed on Chantix, but quit drinking. And now, he said, "I've actually been much better."
Rathbone, meanwhile, has gone public with her suspicions.
"I'm completely in shock. I'm devastated and sad. I lost my soul mate. Where do you go from there?" she said.
But now, she said, "I definitely want people to learn from his death."
Pfizer said it is investigating the case and is committed to the safety of the product.
If you experience serious side effects while taking any medication, report them to your doctor and the drug manufacturer.