Do women use this as a shittest or is it a legit reason for them to reject an invitation for a date?

I ask because I recently encountered this and despite being reasonable aware of TRP logic and strategy, this one confuses me.

My account was a girl I met while jogging, we hit it off with good chemistry. She was new in town, previously living in a nearby city with her now ex-boyfriend. I got her contact info, lingered for a bit talking while in front of her house (did not try to get invited in as I was sweaty and had to work on an assignment deadline that night).

2 days later I asked her to go for a drink, she responds 24 hours later with "Hii, I've thought about it for a while. But my LTR with my ex ended not too long ago and I'm honestly not yet ready for dates n stuff. So I would like to run into you while jogging again, but that's all for me for now. Sorry!" ~Translated as well as I could, the 'for now' in the last sentence is a more casual word in my language that's easily tossed in without having to have a lot of meaning.

Is it a full on rejection, is it anti-slut defense, is it legit?

I'm personally inclined to say that it's a valid reason that I can understand coming from a rather decent-seeming girl, but even in that case I wouldn't know how to deal with it.