>> that's life-changing. >> it was tough. >> did she seem depressed about the weight gain? >> absolutely, yes. >> reporter: her cousin recalls chris said he didn't mind what size heather was. a few years into their relationship, he asked heather to marry him. and it seemed his love didn't waver as the numbers on heather's scale only continued to rise after the birth of their two children. >> did he make her feel good? >> yes, she felt beautiful. she felt loved. she felt wanted. she felt taken care of. >> reporter: chris also took on the role of stay-at-home dad while heather worked and attended college part-time. >> it took her about ten years to get her degree from college, and it was almost to the day that she graduated from college that everything changed. >> reporter: at one point before graduation, heather tipped the scales at 400 pounds. but diane says that hard-won diploma now became a roadmap for heather, pointing her to a brighter and lighter future.