Since the Han family was in a crisis, Han Wanling was willing to ignore her personal feud with Han Yaotian for the time being because she needed him.
In the end, if she wanted to make a comeback, the Han family had to recover first of all.
Naturally, if the Han family didn't recover, the parties for ladies of rich families wouldn't be sending her invitations her any longer. However, she was still the heir of the Han family. The family would eventually one day be hers.
The only thing necessary for that to come true was that she had to take care of Han Yaotian before she could inherit the family.