The 'We're the Millers' actress gave her first post-engagement interview to close pal Chelsea Handler and couldn't stop herself getting teary as Chelsea gushed about what a great couple they are.
The 'Chelsea Lately' host said: ''He's the greatest guy ever. You guys make the greatest couple ever.''
Jennifer admitted she was overwhelmed, saying: ''I just got verklempt [Yiddish for overcome with emotion].''
Justin asked Jennifer to marry him on a romantic dinner date to celebrate his birthday at a New York City restaurant in August.
The surprise proposal - which took place just over a year after they started dating - occurred when the couple were dining at Greenwich Village restaurant Blue Hill.
Announcing the happy event, Justin's publicist said: ''Justin Theroux had an amazing birthday on Friday, receiving an extraordinary gift when his girlfriend, Jennifer Aniston, accepted his proposal of marriage.''
After the proposal, an ''overwhelmed'' Jennifer - who was previously married to Brad Pitt - called her close friends and family to share the good news.
A source said: ''Just after Jen got engaged, she called all her friends and told them about it. She was so happy and said she loves the ring. I think she was overwhelmed and overjoyed by the size and beauty of it!''