The real difference I can think of whenever I watch these two on screen is related to honesty and love.
Honesty: Sai is honest be it with herself or the people around whereas Patralekha is always manipulative. At many instances especially while helping people close to her Sai always prefers to face the storm of consequences for being truthful rather than telling lies for her own benefit. Patralekha's dishonesty for her own selfish gains is clearly evident at every step. She doesn’t even hesitate to cheat on her married partner or make false accusations on the wife of her brother in law. No proof required.
Love: Patralekha is interested in only person that is her brother in law Virat. Her love is only an obsession whereas Sai's love is always expansive! Sai doesn't keep any special preferences for people around and also doesn't hold any grudges. She's even nice to people who trouble and mentally harass her on a daily basis. Best example is Patralekha. Even if she confronts them that's only for their abnormal behavior. She simply doesn't keep any sort of enimity and only gives respect no matter how bad they are towards her. Patralekha is quite opposite to this.
What differences can you think of between these two? Do comment!
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