They won't compromise or communicate healthily.

Healthy, engaged, and positive communication is key for relationships. You and your significant other shouldn't find yourselves talking down to or berating one another because, according to Psychology Today, one of the most detrimental behaviors in a relationship is "having angry reactions to feedback instead of being open to it."

This includes the idea of compromise. "Typically, commitment phobics are inflexible and loathe compromises," according to Darlene Lancer, JD, MFT, who specializes in codependency and marriage. "Relationships revolve around them."

[Photo via @meundies]

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