Sudka I have no experience to draw on but also just wanted you to know your post had been read.
I am very sorry your birth mother doesn't want to have anything more to do with you at this time. It must be very painful and difficult. On the more positive side there are other birth family members who accept you and see you.
I have no idea how these things work out in terms of time, it may be that sometimes it takes a long time for people to come around to new things, and it might be that in the future your birth mother may changes her mind and comes round to the idea of contact.
In the meantime, I just wanted to encourage you that there are people in your birth family who have a positive response and also that I am sure you are a lovely person. I say this because you sound caring and brave. Very brave to have tracked your birth family and made contact etc (I am sure) takes courage, so please don't allow this situation with your birth mother to sadden and spoil things for you.
I know you say you can't stop thinking about her and I am sure that is perfectly natural, and you have not done anything wrong, and in fact have done something wonderful (I think) by finding her and giving her the chance to know you.
Maybe she will come round, or maybe in time it will come to be less crucial to you. Or maybe both. But whatever happens, please remain strong in yourself and focus on the good and positive parts of your life.
All best wishes.