It is difficult to know what may be wrong. You seem to recognize that there are potential problems and writing this letter may mean that you are interested in correcting them. I find that to be encouraging.
It is possible that the problems you have described are the result of your lack of a connection with a stable parent. I am assuming that you didn’t have that, given your chaotic childhood. Not having a stable relationship means that you may have never experienced an emotional attachment and thus would have difficulty connecting with others.
Your inability to feel emotions may be the result of a defense mechanism used to psychologically tolerate living in mental hospitals and group homes as a child. For the majority of people, such experiences would be traumatic. One way to cope with trauma is to disconnect emotionally from those traumatic experiences. This happens unconsciously and can result in an overall lack of emotion with regard to many areas of one’s life. Perhaps that is what has happened to you.
The issues you have identified can significantly and negatively impact your life and your ability to develop relationships with others. It is human nature to desire social relationships and without those connections, you will likely be unhappy. My recommendation is to seek counseling. Therapy may be able to correct many of your problematic behaviors and improve your ability to feel and express emotions. The “find help” tab at the top of this page can assist you in locating a therapist in your community. Please take care.