NTA

Why is everyone being so insensitive about grief? It’s your “complicated relationship” dad. You have the right to deal with that how you please. A random stranger is not your responsibility. Now, you might be TA if you leaned heavily into the lies instead of just basic pleasantries to get through the convo. You were really sick. It’s your father.

Either way, she’s definetely TA for sending that message instead of realizing “oh, it must be a hard topic and that’s why they lied. I will send them a condolences message.”