How should I(24f) gently down a clingy friend(27F)?

I have a friend who we’ll call S for the sake of anonymity. S and I were friends during college, but she graduated and moved to another state so we lost touch for a while. We reconnected in the past few months, and while it was fun at first, I very quickly realized the relationship had become draining for me.

At first, we would just text each other every day reconnecting, and it was nice to have a new friend in my life. Within a few weeks, I realized that S enjoyed talking to me much more than I enjoyed talking to her, to the point where I muted S because she would spam me with so many texts every day. So when she told me she was visiting my city for a week, I was very stressed out wondering if I could stand seeing her for so long when I was already trying to put distance between us.

The week went okay. I ended up seeing S more than I initially planned, but it was still fun. However, I was still drained from spending that much time with S, as well as slowly seeing more and more qualities I didn’t like about her. S and I still messaged each other after that trip, but I was slowly responding less and less while S kept up her barrage of daily texts. I started resenting her, seeing responding to her texts as a chore, and I dreaded having to respond every night. I think I need to tell her how I’m feeling, but don’t know how to say it nicely.

I do want to be clear that I don’t actually hate or even dislike this person. There are some personality traits I don’t like for sure, but no one is perfect. The problem is that I felt like I was her only real friend so I let her message me 24/7 even though I knew it was draining. I would like to continue to be friends, but with more boundaries so that it’s healthy and not just draining me.

TLDR: I resent my friend because they’re clinging to me when I don’t want that, and need to let them down gently.