Often trauma blocking alternates with trauma arousal. A person will engage in high-risk, high shame behavior such as compulsive sexual activity followed by numbing out with food alcohol or something to numb out the shame. Another example would be an addict alternating between ice and alcohol, the former for arousal and the latter to numb out afterwards. When I was using, I used to do speed with alcohol and depressants in order to be "normal!" Not quite.
All the quotations and information not otherwise attributed above comes from Patrick J. Carnes, The Betrayal Bond: Breaking Free of Exploitive Relationships (Deerfield Beach, Fla.: Health Communications Inc., 1997), 12-14.