OP
I was the daughter in a bit dissimilar dynamic.
Hope this is helpful.
this sounds co-dependant / enmeshed. I agree with other posters your first place to start is therapy for yourself. This is great example / modelling for your daughter and will help you with clarifying what is your stuff / what is hers, boundaries.
I did group therapy thing a while ago and was troubled how everyone there was there to deal with problems with their mothers. I asked the therapist how I could be a better mother, was it inevitable I was the person my kids went to therapy about? She said the best advice she had was to work in myself and my own issues.
Have you considered part of your daughters anxiety / depression may stem from your own pessimistic view of her? You are concluding ‘she is not one of life’s happy people’ - that is very damming view of a young person, never mind one you are supposed to love and support.
Maybe she is calling you constantly because she needs something different from you (and maybe not what she’s saying / asking in the moment).
What would happen / what would it take for you to say to her (and before that, believe and feel about her)... ‘you are wonderful. Yes this has been a though time, but you will get through this. You are worthy of love, I believe in you’? Can you discuss this with a therapist? As a young adult it’s not your role to fix details in her life anymore. But it IS your role to not just love her, but believe in her. And it’s doesn’t sound like you do. And I bet she feels that keenly.
Like you, my mum retreated from me as a failure and fuck up, and resented that I wasn’t / couldn’t meet her needs.
All I needed was someone to say ‘I love you, I believe in you, you’re worth it, you’ll be ok’ and she never did.
Can you ‘do’ less about the little details but show your love and belief in her more on the big picture?
Eventually I turned myself around through my own therapy. I came to understand my relationship with my mum was codependent and unhealthy for me. I have successfully redrawn it.
Sadly, my mum is kind of jealous of my happiness. Yes she found fuck up me a burden. But she also found validation in my unhappiness and self doubt which mirrored her own.
It’s worth considering how much your daughter’s behaviour is a reflection of your own beliefs, about her, or you.