Ending it with no ill feeli gs

I have always attracted emotionally needy friends. Fun friends, but emotionally needy. Im a fixer probably to avoid my own issues but thats another story. I met a girl 8 yrs ago. We got along fabulously, went on a trip with our partners all started great. We were inseparable. She then started an affair which is where the neverending drama began. First for 4yrs she had both boyfriends... so our conversations were always me supporting her as she navigated through that. Then she ended up with the second guy and that relationship turned sour. There were a lot of drugs involved and lots of the drama seemed to be made up in her mind. The next few years its been all about supporting her through that... we had a period of about a year that we didnt speak but then I missed her and we reconnected about 2 years ago. She seemed to be in a better spot with her partner and things were good for a little bit till the drama started again. It got particularly rough and she pulled away as she was dealing with it and I didnt pull her back. She has finally ended her toxic relationship because she believed in all the crazy stories she made up in her head. Its been about a year since ive had very little contact with her I tend to get too involved so her dramas take a toll on me till it all just got too much and im quite content with the way things are now. Aside from the dramas and crazy made up stories and need for attention, she is funny, thoughtful and kind but the other issues ended up overshaowing her positives. I had closed my book on her in my mind, no ill feelings just content for us to live our lives seperately. Today, she has contacted me through text and said she really, reallymisses her best friend and that she wants to catch up and that she is happy and im a hole in her life.
Its taken me a back a little. I dont know how to respond. I dont want to hurt her but im not really interested in reconnecting at this time. It makes me feel incredibly **** and guilty and like a bad person. She has gone thru hell (but imagined hell?) and seems to have come out the other side but i the thought of having her back in my life doesnt feel right in my gut. She would be wanting me to write back and say i feel the same but i really dont. Looking for advice as to how to gently break it to her? She did try contacting me a few months back and i ended up writing nothing back as i didnt know what to write... she was still in the thick of her dramas then. I dont want to just ignore her as thats awful and unfair. I also know that its all or nothing with her too... theres no just casual catch ups. Reconnecting would mean going back into a fulltime friendship which im not feeling right now. Any advice? Anyone been in a similar situation?