Just found out that I have a half-sister out there somewhere........

Shocked, It is nice of you to share your story. We met in chat the other day. As I said to you then as now I hope you and your mom will give her a chance. She may only want medical history or she may want to get to know your mom and you. As Dpen6 stated in her message you can't go back which is true but you can go forward. This is a rare opportunity you have she is after your half sister biologically. I think once you and your mom get over the emotional impact of this I believe strongly that something good will come from this. As an adoptee I ask that you give her a chance she had no choice in her adoption. she is not a secret she is a human being afterall. As I was saying to you the other day put yourself in her shoes. How would you feel if you were her. Anyway take your time this is a very emotional period don't rush it. It can be a very exciting time wow to have a sister could be pretty special. One last thing don't expect much from this but be pleasantly surprised if things do work out. I wish you and your mom all the best. I know in my heart you and your mom will do the right thing. Take care and God bless!