She and Abhi have nice moments in the past, but really, their journey has always been of struggles. The only nice, stress-free time they've had is during the kidnapping track (how ironic!). When he was really nice to her in the beginning of the pregnancy track, while she was still Fuggy, it was more his gratitude for her helping him keep the Tabhi baby a secret. He was scared to tell Daadi the truth, and regardless of whether it was a good/bad idea, Fuggy helped him keep it under wraps for as long as possible.
Besides those two sequences, she's never shared a relationship with Abhi where he wasn't under some misunderstanding about her, either due to what was put in his ears or what he thought up himself. He's usually ended up getting angry at her and her voice has usually never held power in the past.
Setting that aside, Pragya also doesn't seem to have a powerful male figure in her life prior to Abhi. They never speak of her father. She had a few marriage proposals that come and went. Tarun ended up wanting her money rather than her. Suresh wanted Bulbul. And so when she married Abhi, I'd assume there would already be that sense of anxiousness as to how he's going to be as a husband, how she's going to keep him happy, having nothing to compare it to. And to top it all off, it turned out to be a revenge marriage.
Random side note, but she also saw her mother get anxious/fearful over the littlest of things when Abhi is just a tad bit upset/angry. Sarla made it seem like Abhi should never get mad or else...
I think for all those reasons, plus her misplaced trust in Daadi, it has caused her to have such dreams about Abhi.
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