Suman has always been toxic since preleap she was horrible to dhara who was very scared of her so I'm assuming since dhara was a kid suman has disliked her. Then postleap she mellowed a bit but she was horrible to mama and mami about raavi Dev marriage. Yes they destroyed her life but suppose raavi and Dev loved ea and her family would have to beg so that they could marry suman again displayed her toxic behaviour. Then in haveli she might have been nice to raavi but it was coz of shiva otherwise whenever she was fighting with mami she would also taunt raavi and make her feel bad about her maayka. Post haveli she was fine for the most part till she got the lame taunts over grandkids and then she faked a suicide attempt and mentally tortured dhara especially about a kid and before that she sold those kangans that meant so much to shiva and nearly broke shivi up just so she could get gaura to give her a grandkid ugh we know what she did post slap coz then her true colours started to show she will always be the guys mom and nothing else.