Everyone goes through challenging times. But when behavior shifts dramatically and deviates from what's been normal for so long, something is amiss. This might show itself through passive-aggressive behavior, a reduction in communication, or a lack of including you in plans. It also might show itself in a change in his use of technology: Long delays in responding to your texts or messages, or a sudden change in his profile picture (or hiding his relationship status) are both tell-tales signs that something's not right.