My mom put my kids in danger or am I being sensitive?

I’m pissed. My mom wanted to help me after my baby was born so I asked her to quarantine for 10 days before coming to stay at my house. She said she was going to do it. She was supposed to start June 26th and come come over July 6th-13th.

But instead she was able to get a Covid test on June 26th. I told her to self quarantine until she got the results. That included grocery shopping since she likes doing it everyday. I was very iffy because she constantly lies but I decided to trust her on this. She got her results July 1st and come over July 2nd. She went back home and came back the next day I told her that she couldn’t be doing that because my dad works with my cousin and brother who does not give a shit about Covid. We had previously agreed she was going to stay at my house the entire time. Well she didn’t come over the weekend until Monday. While she is staying here I heard her talking about someone feeling better I asked her what was going on and she finally told me my sister in law and nephew were sick and sounded like Covid symptoms. Anyways Friday came and she said she had to go home to my dad. She asked me to send some pictures and she was not getting them so she gave me her phone to see if something was wrong. During that time she gets a text from my sister in law and I accidentally opened and I saw an address of a river and some pictures of them there on July 1st. Nothing clicked at the moment. So a couple days go by and mom is telling that my sister and law and nephew are still sick. I asked her when was the last time she saw them and she gave me a bullshit answer. Then I was like are you sure it was a long time ago? And she replies with “omg here you go again. We don’t know if its Covid or not” I decided to ask my little sister. I pretended I knew and asked “how was the river last Wednesday?” And my sister went on and told me innocently. I decided to keep it to my self until their Covid results came which was positive.

I confronted my mom and she did not let me talk. She just kept on saying i was being a drama queen and to thank god I don’t have it. She was trying to literally pick a fight with me. I feel so betrayed. I told her I did not wish to ever speak to her because she put my newborn who was born with a heart problem in danger just because she wanted to go have fun.

Oh and while she was staying here my husband cleaned her car in and out and found receipts of her going grocery shopping everyday during the time she was supposed to quarantine.

I specifically told her if she couldn’t quarantine that I understood and wouldn’t feel any type of way about it. I just wanted my kids to be safe.

Am I being an unthankful bitch?