Am I overreacting?

I have been sick almost my entire pregnancy. I have lost 20 pounds so far and I am 16 weeks pregnant. For the sake of privacy we will call this person Lisa. Lisa was hosting a party that was a good distance from where my husband and I live, and due to weather conditions and the way I have been feeling lately we decided to stay home. I found out today that Lisa has been running her mouth about me and saying that I haven’t even been sick and that I use it as an excuse. She isn’t talking badly about my husband at all, but she is blaming the whole situation on me.

How would you feel about this / go about reacting? I know stress is bad for the baby, and my husband says that he isn’t concerned because everyone else knows I have been sick and won’t believe anything Lisa says, but I just feel so depressed over this situation.