Demi wore a strapless gown and had her hair sleeked back with a large veil at the back, while Andrew looked dapper in a Giorgio Armani tuxedo.
Her former H&A co-star Georgie Parker, who plays Roo Stewart, shared her well wishes, writing: "Sweetheart, congratulations to you both. What a beautiful picture."
Fellow Summer Bay alum Cassie Howarth commented: "Congratulations Demi!! Beautiful!"
After leaving the soap, Demi moved to the US where she met Andrew, who worked as an assistant producer on Modern Family.
The couple, who went public with their relationship in February 2018, began dating shortly after Demi split from her Home and Away co-star Alec Snow, who she dated from 2014 until late 2017.
The pair reportedly split after she moved to America to pursue her career in acting, later telling New Idea that breaking into Hollywood is much harder than she expected.
"It's a whole new ball game in terms of acting. I have high hopes and it's just a matter of time," she said.
"It's hard but it's all worth it, and it's exciting because my career can go from nothing to everything very quickly."
The 28-year-old actress announced her engagement in July 2019, revealing that Andrew got down on one knee on Independence Day.
"Just said yes, FOUR-ever! #happyfourth #brooksfourlyf," Demi wrote captioned an adorable photo of the pair together, showing off her dazzling oval solitaire diamond engagement ring.
This story originally appeared on our sister site, Now To Love.
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