It was not long ago that Spears, 39, who is going through her conservatorship battle, praised Asghari, 27, for sticking by her side.
"Things are evidently becoming better for Britney with her conservatorship and she's never felt this liberated in all aspects of her life," the source continued.
"The closer she gets to freedom, the closer she is to seeing all of her dreams become an actual reality. Marrying Sam is high on that list and loving him the way she wants, how she wants, on her own terms. Sam also understands how close they are to being out of the woods, and it's definitely motivating him to think big."
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