Mental Health Support

in your life and you have some problems you don’t want to talk about ( no need for her to know her constant need for attention is one of the main ones ) and so you won’t be able to reply as often but let her know you love her but gently put her on notice that it is you who will try to keep in contact as much as you can for the near future.
Boundaries have already been broken and must be reinstalled firmly but gently
That way you decide when you want to deal with her instead of always having to answer & respond on her timetable.
Hopefully this will set a new pace for how often you contact each other as time goes on

If she is upset ask her to understand as you have tried to be there for her a lot but now your own issues are important (even if that issue is just you not dealing with her but remains unnamed)
If she can not understand that or won’t back off , then well there are deeper problems with displaced anger beyond your capacity to handle

She will find some other outlet or person to voice her frustrations I bet and you seem to be done with playing that role - it’s your life
live as desired imo