"It's hard sometimes when the doctors come in because they look at my scans, and I know they don't look good," said Kettel.
The 36-year-old mother of two has stage 4, metastatic colon cancer.
"I've been through 13 rounds of chemotherapy within the last seven months, I think," said Kettel.
Instead of crying, Kristin laughs with friends at her "chemo parties." Each one has a theme, and it has nothing to do with cancer.
"Getting through chemotherapy alone I consider a success. It's because I have had a positive attitude," said Kettel.
But can that attitude affect the outcome of disease? In a Johns Hopkins study, researchers followed nearly 600 people with a family history of heart disease. Those with a positive outlook were half as likely to experience a heart event.
"Attitude is all the difference in the world. Attitude is a choice," said Dr. Robert P. Shannon, Mayo Clinic.
While scientific studies on cancer show mixed results, one found breast cancer patients with feelings of hopelessness are less likely to survive.
Marilyn Wattman-Feldman says her upbeat outlook may not cure her stage 4 breast cancer, but it's made her physically and emotionally stronger.
"I had to look at everything, even the chemo treatments, and find something funny about what was going on as hard as that was," said Wattman-Feldman.
All this new research doesn't prove attitudes affect health or cause illness, but many researchers prefer to believe the glass is half full and the association is worth further study.
A recent study of healthy women found optimistic women had a 14-percent lower risk of death from any cause after eight years compared to those who were more pessimistic. More cynical women had 16-percent higher risk of dying than more trusting women.