If there is an issue of why someone else had been promoted you are within your right to ask your supervisor for feedback.
Staring is not always a sign of affection; it can be a sign of intimidation quite common in the animal kingdom (people being higher order animals)
It is doubtful that she feels shame for promoting someone else. After all, that is an administrative decision- of whom to get promoted.
When someone is attracted to someone else they show positive regard/attention not negative.
Try not to take the passing of a promotion personally although it feels as an attack on you person it is only a professional decision. Find out what the other person is doing differently and what they were looking in when promoting him.
I understand, but she told me I was special to her and she blushes when I am around and will not make eye contact. Also she allows me to get away with a lot why others are not. For instant the yelling. My boss is tyrannical. She yells at others for little things but no matter what I do she has never yelled at me.
I understand positive regard is what you show when you like others bnut some people are dysfunctional and they don/t always know how to show their feelings she is one of them.
The yelling on her part is unprofessional. Avoiding eye contact can be as a result of being timid along with the blushing yet, there are mixed messages being sent on her part. She may be someone who when not reprimanding you (since you've mentioned getting away with things that others get in trouble for) because you're a valuable employee and she trusts you to correct certain behaviors/things on your end. Hence, the compliment she had made. Unless you ask her directly about her motivation for her behavior, you can only speculate about it.
Work related romance is never a good idea though. In the long run someone gets hurt. You would not want to be involved with a supervisor because if in an intimate relationship she can still treat you as a subordinate and that is not healthy. A healthy relationship is one where the two partners are equal to each other.
If she is tyrannical even worse to become involved with her.