Brady, please listen to me because what you are doing in more dangerous then you could imagine. First of all there are two things called anorexia, one is Anorexia Nervosa and then there is physiological Anorexia. Anorexia is defined as a lack of normal appetite. If it is caused by a desire to lose weight as a result of unhealthy body image it is Anorexia Nervosa. If this is the case then it is it's own illness. If it is caused by another physical illness or medication then it is Physiological Anorexia and is a symptom of a larger concern that may be highly treatable.
Now there are many cases of misdiagnosis of Anorexia Nervosa when the true cause was physical but from what you are saying to me it sounds like Anorexia Nervosa. You need to go to your doctor to make sure though that there isn't a physiological cause. For the purposes of this post though I will assume Anorexia Nervosa. While many doctors would say you can't diagnosis this disorder if the person a) still has their mens or if they aren't refusing to maintain a BMI of at least 18; I personally think that is foolishness. If you went to 105 you would be under this BMI and officially qualify for Anorexia Nervosa diagnosis. Even people who maintain higher BMI (18+) are at increased health risks though.
For a minute though I would like to leave the realm of pounds and inches. Brady, you have already loss an excessive amount of weight and your goal to lose more because of your discomfort with your body smacks of Anorexia Nervosa. You state that your partner and family are worried about you, you voice a lack of insight of how your own body should look/ be and you want to go further in spite of this. These are all hallmarks of Anorexia Nervosa and sadly just because you say you don't have it means little, the signs point to this and warrant further investigation by professionals.
Now FTMs are at high risk for eating disorder because of GID and the discomfort with their bodies. I am not arguing that you should be comfortable with your body but I am arguing against a disorder that has the highest mortality rate of any mental health disorder. If this is the case then hormones can help but as long as you think that it is better to hide your body then to be healthy you will be in a bad place and need help. Men aren't really supposed to be skin and bones (and neither are women), testosterone use usually precludes this unless you are ill or starving.
I would really suggest that if you are going to have a body dysmorphic disorder that you pick something involving staying in shape. Choose roles models who are fit and healthy. People like Lance Armstrong are good choices because while they might be viewed as skinny they are in truth very healthy with a strong body. Some people just have an obsessive personality and if you must obsess then obsess about being healthy and in good physical shape, not being skin and bones.
I am worried about you because the path you are choosing is dangerous and is grounds to refuse to allow you to transition which would most likely be even harder on you. I would like you to get to your doctor and tell them the truth. You can address this with the proper support, professionals and a willingness to get better. The longer you do this the more likely it is to be fatal and untreatable. I am not joking here and I encourage you to continue to talk about this because you are valuable and deserve to have a healthy body. It isn't an easy path but it can get better.
Finally in answer to your questions, your current weight is borderline underweight. I don't like it. It will become harder to pass as you lose weight because men typically aren't that skinny. Your chest will remain and your hips might decrease but odds are you will be lose more muscle mass. This will also tend to out you. Losing or gaining weight is usually a poor way to hide your curves. You already pass without screwing your body up. You are showing signs of an eating disorder and need to get assessment and treatment. Brady get some help, ok, buddy boy? Incidentally we are the same height and I am trying to maintain 135lbs. I have physiological Anorexia that was misdiagnosed as Nervosa. You aren't alone unless you hide from yourself.
->-bleeped-<-boy