((Data)),
I have to apologize, I was going to address that part of your post and I was interrupted and did not get a chance.
I am very sorry you got such a cold response when you contacted your birth mother. It's unfortunate that you don't have her history either so you can better understand the reason for how she responded. There are times when a woman gives up a child for adoption that has a lot to do with her mental health and whatever she may be going through in her life at the time. Her distancing could be a lot more about not wanting to think about that time in her life then "your" worthiness and curiosity about who your birth mother was. When a woman talks about feeling a child she gave birth to is not "mine", that says a lot about where she was mentally at that time. This NEVER means that child did not deserve to be loved. It's understandable how difficult this is to wrap one's mind around, especially on an emotional level.
Some women "need" to distance from giving a child up, too hard to revisit in any way. Again, no bearing on your worthiness. You responded the right way, and it's possible this woman may change her mind too and at some point reach out to you. That really depends upon where she is "now" in her life. Give yourself some "kind/caring" thoughts towards not allowing yourself to think of this as a rejection, that can be a challenge that can take you some time to work on.