I asked my sister. It was DV between husband & wife only. Some cases husband abusing wife, and in some cases actually husbands were victims - their wives abusing them.
There was nothing about in-laws DV. In YMGGK, DV is from daaima to lata. (yet they are not actual saas bahu, only because Raj considers daaima as his mum). So in the show it is a different version of DV which happens out there in the world.