WIBTA If I lied to my fiancés mom about coming to visit?

My fiancé and I just had a baby in November and we’re still figuring out life. My fiancé is on a work trip and won’t be back until tomorrow evening and immediately has to return to working overtime. I’m overwhelmed as it is and am not looking forward to company.

This lady has dropped in twice with short notice and without clearing with us if we’re okay with her visiting and she also stays for such a long time (3 plus days). I have nothing to talk about, I smell half the time because I can’t always shower when I want and my hair is starting to get matted. It’s just bad right now. We tried telling her we would rather have visits when our baby is 6 months old but she does not listen. I have told her the pediatrician doesn’t want us having visitors until flu season is over and she completely brushed it off.

I haven’t spoke to her since Christmas and she sent a New year text but I ignored it. Her birthday is tomorrow and I’m thinking of calling and lying saying we’re all super sick but I’m not sure that would stop her from coming! I don’t want to make her sad on her birthday but I really am not looking forward to this visit and I am adamant about putting my foot down when it comes to her disrespecting our boundaries. I feel conflicted but my fiancé is all for it.

My family members have reassured me that we can make this decision because it is our baby and so have my fiancés. I just wish she would ask and not decide when she could visit as it is never looked forward to.

I don’t want to be a bitch but I don’t want her coming.

Context; she was the last to be told about the baby but still. My MIL does NOT know what boundaries are, no to her means let me work my way in.

Our baby’s pediatrician told us not to have people around, I didn’t make that up as an excuse.