I'm not sure the slap here qualifies as "abuse". I volunteer at a women's DV prevention and help charity in the USA which mostly deals with south Asian women, and based on what we go by anurag's slap would not qualify as domestic violence or abuse just like how prerna's slap didn't qualify as abuse when she hit Anurag for marrying komolika.
A slap becomes an abuse when it is used to exercise control and kind of make life hell for the spouse - any slight deviation from expected behavior makes an abusive spouse (usually husbands) slap their wives and there is such a humungous fear in these women - it is incomparable to the fictitious situation that our story leads are in!
Prerna is clearly not a victim of abuse here based on real world laws :). Yes it is completely incorrect to get physically violent with anyone - and no one condones that but not all situations of physical violence qualifies as abuse.
When some person provokes you to such an extent - it is only human that the one on the receiving end might respond with their reflexes before their brain can control their action - in such situations we are told to strongly assess the situation and find out from the complainant as to how often they encounter such situations and under what circumstance the violence was perpetrated, how frequent it is and so on.
So let's not label anurag's slap as abusive. Prerna is NOT a victim of any sort of domestic abuse here (yet). Now if Anurag continues to stalk her/harm her and the likes after she very clearly tells him to stay away - then it would (in a real world situation) help if prerna files a restraining order against Anurag.
We are explicitly told to analyse situations fully before deeming something as abuse - so just thought i'd share since I have first hand experience dealing with a lot of women who immigrate to the USA and who suffer at the hands of controlling husbands!