I went on two date with a girl, the first one was enjoyable even if i failed to escalate in any way, i just enjoyed her company and was fine with it.

The second date was plain terrible, she was boring, and when i thought about it after she pretty much insulted me for everything i told her about myself. And there was definetly no IOI on that day. Two days later (Today) she texted me to ask if i want to go out with her again, i didnt respond and she send me another text at the end of the day saying i could at least say no.

I don't want to explain myself or start to say mean thing to her. Should i just ignore her or send her a small but okay message?