We did raise our children together, but ended the marriage after 30 years. We do get to share the joys of our grandchildren, but as friends rather than partners.
Through the process of our difficult marriage, and my 43 years of counseling individuals and couples, I learned much about why it is better for some relationships to end.
Physical and/or Verbal Abuse
If there is physical abuse or severe verbal abuse, this relationship should end. It is never loving to yourself to stay in a relationship that is physically dangerous to you or to your children. Nor is it loving to yourself or your family for you to be consistently subjected to intense, heartbreaking verbal abuse.
Everyone deserves to be loved and supported for who they are, and if you are with a partner who cannot do this, then you need to love and support yourself enough to not be subjected to abuse.
Addictions
Substance addictions such as alcohol or drugs that interfere with the ability of you and your partner to connect with each other can cause much loneliness and heartbreak. As much as you and your partner might love each other, you deserve to be with someone whose love is reliable.
Process addictions, such as a gambling addiction that threatens your financial security, or a sexual addiction (porn, affairs) lead to much heartbreak and lack of trust. Affairs can also lead to physical danger, due to sexually transmitted diseases. Unless your partner wants to heal these addictions and is receiving help, you will continue to suffer and be at the mercy of the addictions.
Personality Disorder
While personality disorders such as Narcissistic Personality Disorder (NPD) or Borderline Personal Disorder (BPD) can be healed, it takes much motivation on the part of the person with the disorder to heal it. If there is no motivation to heal, then being at the other end of the anger, neediness, control issues and crazy-making may not be healthy for you. Expecting someone to change if they are not receiving intensive help is completely unrealistic – you will wait forever.
Growing Apart
People are attracted at their common level of woundedness or their common level of health. If you and your partner were both abandoning yourselves when you met, and if you went on a healing and growth path but your partner didn’t, then it is likely that you have grown apart.
This is what happened in my marriage. As I learned and healed, our formerly codependent system shifted and I was no longer willing to be a caretaker. Our relationship was based on the caretaker/taker codependent system, so when I shifted the system, we stopped being able to connect on the wounded level on which we previously connected. When our relationship reached a place where there was no more learning and growth occurring, and no connection between us, it was time to move on.
No Learning or Growth
One of the great values of relationships is being able to heal, learn and grow emotionally and spiritually with each other. When one partner is not available to learn and grow, the relationship may become stagnant. At the beginning, when there is passion and excitement, it might not be evident that learning and growth is not a priority, but as time goes on you might find yourself feeling sad that you cannot share the excitement of learning and growth with your partner. Sometimes, a partner who is not interested in learning can still be supportive of the other continuing to learn and grow with others, but if your partner is threatened by your learning and growth then it might be time to leave.
I always encourage people to do their own inner work before leaving a marriage, as we take ourselves with us and often create the very same dysfunctional relationship next time. The time to leave is when you are happy within, due to taking loving care of yourself, but you find that your partner is either not willing or not interested in taking responsibility for himself or herself.
Listen to Dr. Margaret Paul's interview with 
