It's a hard path for us parents Ersi. Our hearts do take a lot of blows when our children start the process of detaching from us. Your daughter sounds as if she is aware of the necessity for her to be on her own. Let her go. I know how hard that is, but she is now a young adult and is trying to launch on her own, you may not have been prepared for that launch, but apparently she is. She may decide to come back for a little while, or not, but whatever she decides, it seems appropriate for you to let her go for now.
You might try getting some support for yourself. Therapy, a support group, some safe place you can go to to vent, voice your opinions, cry, get tools for yourself, get empathy and understanding..............get support. Getting support will ease the pain and allow you to see a broader perspective.
Hang in there Ersi, in time this will look a whole lot different. Give it time.
If you could put a signature at the bottom of your post like the rest of us have, it will be easier for all of us to recall your story. Thanks. Go to the top right of the page and click on your screen name. Look for signature, write it and remember to save it.