I fail to see the problem. Her parents consented, after all.
We forget that prior to the 19th and 20th centuries, people frequently married and started shouldering adult responsibilities at 15 or 16. And women often married much older men; such men were thought of as "stable" and as "good providers."
Recall the story of Will and Ariel Durant. She was 13 years his junior, a 15-year-old student at the school where he taught. According to
http://www.willdurant.com/ariel.htm:
"By the time she reached the age of 15, teacher [Will Durant] and student [Chaya Kaufman, later "Ariel"] had fallen in love. Realizing the potential problems that would attend such a student-teacher relationship, Durant resigned his position. . . . Despite some initial misgivings, Mrs. Kaufman in time gave her consent to the union and accompanied Will Durant to City Hall to witness the marriage. Chaya herself almost missed the service, as she had opted to roller skate to the locale and, to everyone’s relief (and after one or two falls en route) Chaya arrived at City Hall – out of breath, but ready to start a new chapter in her life as a married woman."
This was in 1913, folks. They stayed married and (by all accounts) in love and as working partners for
almost 70 years.
Sure, these two in the news story risk divorce . . . but so do couples who marry at 35.