yes, its possible she has another man that she is interested in and you need to protect yourself. another scenario is that she is caving to family pressure. when i told my parents that i was pregnant (and not married) the first thing out of both their mouths was that SOB who got me pregnant wouldnt have squat to do with me or the baby ever again. it was a knee jerk reaction. keep your mind open. try to get her to talk to you, not email or text, but talk to you on the phone. do not send her any emails or texts, as these can later be used against you.
its great that you are getting a lawyer, just make sure its one in CA. dont waste your money on a lawyer in another state. child custody laws are different in each state so you want advice from someone who is experienced in CA law. CA child custody laws are more liberal and if you ask for it, you can expect to get 50% physical and legal custody of your child. she would have to prove that you are negligent for you not to get it or that you are not capable of taking care of the child.
remember, this isnt about you or her anymore. its not about who wins or getting even either. everything you do should be in the best interest of the child.