My heart is always hanging on someone else
They haven't answered, and you've already reached the worst case. Your child goes out and your heart won't land until they're home. A relative's test results aren't back and you're sleeping worse than they are.
You know you're overthinking it. And that suspended feeling isn't something you can reason your way out of.
Sometimes you even feel that worrying like this is part of the love — that not worrying would mean not caring enough.
What may be going on
Worrying about the people you love is natural. Worrying until you can't be steady, though, has gone past care and become a habit of rehearsing disaster on their behalf.
It isn't necessarily easier for the person being worried about either. They often feel the tension, so they report only the good news, which makes closeness harder rather than easier.
Drawing your heart back a little isn't becoming cold. It's steadying yourself first, so that when something does happen you have the strength to be there.
Essences that may fit
You don't need all of them. See which description comes closest to how you are now.

Red Chestnut
Over-worry for others
Over-worry for others; the heart always hanging on someone else. It accompanies you as attention comes slowly back to yourself — it isn't asking you to love less.

Olive
Total exhaustion of body and mind
If long caregiving has spent you to the floor, tending your own exhaustion first is the practical move.

Chicory
Possessiveness, love with strings
If the worry also carries "I want them to do it my way", look at this one.
One small thing you can do now
Put one hand on your chest and one on your belly.
Don't adjust your breathing — just notice which hand moves more.
When your heart is suspended, this brings attention back from "how are they right now" to "I am here right now". A few breaths is enough.

When your chest is tight and you can't stop
Neiguan PC-6 · Inner wrist
