Obviously, giving in to sexual advances from a boss is not an appropriate method of improving one’s performance in the corporate world. The “testing” that he talked about was an attempt to rationalize his illegal behavior. In the United States, his behavior would be considered sexual harassment.
Please don’t be so hard on yourself (i.e. how can I be so desperate?). It is human nature to want to be wanted and loved. I think you have great insight into why you feel the way you do. Your past sexual abuse has a lot to do with your feelings. In addition, low self-esteem and feeling unworthy makes you vulnerable to people who might be seeking to take advantage of you.
Counseling is the ideal place to deal with these issues. If possible, choose a therapist who specializes in trauma and sexual abuse. Counseling could help you deal with the feelings generated from this event and to develop a healthier sense of self-worth so you will choose the right partner. Please take care.