Suchitra is a pacifist who believes in forgive and forget principle and wants peace at any cost. No wonder she readily invited Durga.
Atominis, the word for people like Suchitra is- Non conflicting: people who do not like any kind of conflict in their environment. Your analysis of her personality is spot on based on what we know until now. I personally do not like such people because in the bigger picture, they could be projecting themselves as peace loving and helping maintain the calmness, but in doing so they are helping the bully to remain a bully and a weaker nicer person to remain the same. It allows the environment to settle outwardly at the surface but deep down the volcanoes are in the making that could erupt anytime.
The biggest example would be Nitya/Durga. The right step by Suchitra, being the eldest in the family ( in relations) if she had taken control of the situation with Shaurya and his gang or had given protection to the sisters, she would have had created a divide in her family but the volcano ( Durga) would not have generated.