✔ 最佳答案
Everything you feel right now is ok and allow yourself to feel it. Overwhelm and shock may be two terms to explain this.
Your friend is a dear friend and will continue to be. Your half sis/friend's foster sis on a universal level your paths were meant to cross.
It is likely you both had challenges on the path of life so once you get past the initial shock you will begin to see where this takes you.
Your friend remains a friend and the degree this half sister comes into your life time will tell.
Good luck