But despite going to extraordinary lengths to freeze her eggs two years ago, that dream slipped away on Aug. 17, when the MTV reality star, 34, underwent an emergency hysterectomy after learning her cancer had returned for the third time.
"When I came to, they told me that they couldn't save my uterus," she tells PEOPLE in this week's issue. "That was a blow. We'd fought so hard to keep it. Might sound silly to most, but it's what made me still feel like a woman and gave me hope for a future. I felt empty ... gutted."
In addition to a tumor blocking her colon, doctors found cancer in her stomach lining, and Brown now has a colostomy bag. A second surgery followed three days later due to complications from the first.
"I was completely defeated, honestly," says the recurring Real World/Road Rules Challenge contestant, who candidly chronicled her 2012 cancer journey in a blog for PEOPLE.com.
But when her medical team explained how "touch and go" her second surgery had been, "it put things into perspective," she says. "I might not have the ability to ever carry a child and I have this damn bag for the time being – but I'm alive."
Reporting by MICHELLE TAN
For much more on Diem's cancer journey, pick up this week's issue of PEOPLE, on newsstands Friday