As we say before, if a relationship starts with signs of physical violence or sexual violence it may be easier to finish it from the beginning, but the subtle manifestations of psychological violence can make it an entrance door for other violent situations.
The degree, so to speak, of violence is not related with its kind; psychological violence can be clearly as dangerous and painful, or more, than physical violence for example, but those subtle manifestations that it includes can be harder to identify in the beginning and, therefore, easier to accept and enter in the spiral of violence.
A spiral where the further you fall the harder it is to leave!