An acquaintance keeps wanting to talk to me because she likes having a good listener for her to talk lots about herself, but I sincerely have no interest in using my energy to feed her ego. How do I kindly convey my lack of interest so that she stops trying?

As written in title. I have tried hinting this person by responding very slowly to text messages (ranging from several days to a week), sometimes even not writing back after reading. But the person seems to not get that I don’t find talking to her very fun. I think my radar somehow picked up that she’s more interested in talking about herself than knowing who’s on the other side. She asks “How are you” just so that she can start talking about her status after you politely ask her back how she is. I’m not interested in babysitting her ego, so I hope she finds an audience somewhere else.

But I’m having a bit of trouble thinking up a way to convey my feelings in a way that’s not hurtful. Just me saying “I’m busy” is probably not enough because I feel she’ll then try again some weeks later. It doesn’t mean that we can’t be friends, but I’d rather prefer that we stay distant acquaintances who barely know each other. Or we can reconsider once her ego is able to see other souls as equal beings instead of fuel for herself.

I was wondering if I could get some tips here?