Adopting an adult?

Anyone ever heard of someone adopting an adult? I feel like I wish I could be adopted even though I am 35. My parents let me down in life and I have never had the support of loving parents. I have had to support myself emotionallty and financially.
I have made sooooooo many mistakes trying to learn how to do this. How does a child learn about life when there are no role models or negative ones.
I feel like I had so much potential wasted by time lost.
Yes, I am slowly, slowly realising how to live life but I feel so alone and wish I could call a mum or a dad and say this is happening to me. Help.
I am just voicing this thought. I it have when at my lowest like now.