An unhealthy or bad relationship is characterized by a cycle of violence. The abuser uses disrespect, fear, jealousy and possessiveness to create an imbalance of power. This is abuse. The cycle is difficult to break once in motion.
Look for cycles of violence to include these elements:

Tension: Criticism, yelling, swearing, angry gestures, coercion, or threats
Violence: Physical and sexual attacks, or threats
Seduction: Apologies, promises to change, or gifts


These elements keep the cycle in motion:

Love for the abuser: Believing that the relationship is not entirely bad
Hope: Thinking things will change or it's just a phase
Fear: Worrying that threats will become a reality

(Adapted from Dr. Lenore Walker's "Cycle of Violence")
I don't particularly like David, but we both play in the same band, so we're together more often than I'd like.
 

If these elements sound familiar, how many of the warning signs do you also recognize?

Or, if these traits do not sound accurate, see the characteristics of a healthy relationship.