Do we just not focus on her behavior and hope that she'll get past it?

My daughter R will be 5 in 5/01. We have had multiple changes in our family, including the death of my father suddenly and a very close aunt and uncle, and the fact that a close sister in law is no longer babysitting twice a week. SM was brought to our attention by a pre school teacher 1 year ago. We are seeing a neuropsychologist who has been helping, but there doesn't seem to be very many people who have even heard of SM. We have been educating ourselves and everyone around us, hoping that because she is so young we could get a head start on helping her instead of just waiting it out, but we have so many questions. R has made significant progress--she is a ball of fire at home with us, and has started to whisper to her grandma. She talks to some of her peers, but to no other adults. She has never talked in preschool and our concern is the upcoming start of kindergarten. We have talked already to the school psychologist and have requested the same kindergarten teacher that my son had (he's 7), hoping that the familiarity with the teacher and the classroom would be helpful. They both seem very willing to help! She shows no signs of any other "problems". She is developmentally where she should be and her speech and vocabulary are excellent. She has made strides socially--she is quite popular with her peers, she is compliant in every aspect, she has eye contact with those addressing her and she actually is a show off with her gymnastic skills and just being silly. She just doesn't talk!!!!!!!! We are concerned that she has fallen into a "comfort zone", and that she doesn't need to verbalize because all of her needs are being met and she has mastered the art of non-verbal communication. Our therapist feels that she is past the "major anxiety" issues and that there is a lot of manipulation going on. I'm not so sure. We have tried behavior modification, forcing the issue, bribery, etc. with no success. She closes down completely if we pressure her, so we have decided to drop the issue or just not make it such a big deal and it seems to relax her. The therapist feels that we should start depriving her of privileges, and start some hard core behavior modification or meds. We don't feel that we have exhausted all of our options yet, and she really has made progress. Do we just forget about it and hope that she'll just get past it? Do we try modifying her behavior by taking things away from her?? We don't want to do anything that will harm her in any way--she is so precious. Please help!!