The second sign that can signify danger in a marriage is if couples stop investing in each other. I presented this topic previously as reason for high divorce rates, https://twobecomingwon.com/2015/07/15/marriage-investment.  

In order to get a return on any relationship there must be some sort of intentional investment. If the only time a husband and wife meet is after work in the evening’s for dinner, and the rest of the time is filled with children activities or home projects, there will not be much of a foundation to build upon.  
We all have a need to feel loved, accepted and valued. This is especially important in a marriage. Failure to invest in these needs leaves your spouse’s “marriage bank” depleted. When the emotional needs bank is running in empty there is room for bitterness, resentment and lack of intimacy. When these items are continually deposited into this “bank,” disappointment and desperation can set in.  

This can be, and usually is a slow fade. We will reap from a relationship what we sow. How are you investing in your marriage or relationship?