I pride myself on being able to resolve most issues that come up in my life. I generally have the right tools, and I'm successful in making a repair or finding a solution. As a matter of fact, there have been very few circumstances in my life that I haven't been able to "fix."
This all changed when my marriage ended. My inability to repair my marital relationship was both humbling and frustrating, and I berated myself for a very long time for not having the proper tools to mend something that was so apparently broken.
I figured I had a couple of options. I could hire someone to help me mend what was broken (like a therapist or coach) or I could search for the tools I needed on my own. I ultimately did both, and while there was a lot of trial and error, I think I honed in on some truly essential tools that ultimately repaired my broken heart.
Here they are...
Self-Compassion 
"If you begin to understand what you are without trying to change it, then what you undergo is a transformation." -- Jiddu Krishnamurti
The idea of being kind to yourself may seem obvious, but you're probably treating yourself more harshly than you realize. Without self-compassion you will judge, blame, and ultimately stay stuck in your negative feelings. Self-compassion will break your heart back open, and ultimately bring you internal peace. Speak to yourself like you would anyone else going through what you are experiencing.
Empathy
"The great gift of human beings is that we have the power of empathy." -- Meryl Streep
Similar to compassion, empathy can deepen self-understanding as well as your understanding of your (ex)partner's experience. You may be holding the presumption that you know what your (ex)partner is experiencing based on what you're feeling, but everyone has their own unique internal process. Empathy promotes the ability to see that your feelings are different, and that there is no right or wrong way to be through the process of marital dissolution. You don't have to agree with his or her point of view, you simply have to understand how they could see it in their own way.
Courage
"Courage is grace under pressure." -- Ernest Hemingway
Courage can be defined in many different ways, but in this context it's the willingness to show up and be present in spite of the pain. Running, avoiding, shutting down, and alienating are all ways to defend against what you don't want to face. Courage brings you closer to resolution and healing. It's taking the opportunity to stand tall and proud even in the face of something that feels awful.
Mindfulness
"Be happy in the moment, that's enough. Each moment is all we need, not more." -- Mother Teresa
The ability to focus and concentrate becomes challenged through the process of divorce because you are being emotionally pulled in a million different directions. Mindfulness is about slowing down, acknowledging what's happening without judgment, and remaining present even in the face of adversity. Trying to be present on a moment-by-moment basis reduces stress, and helps you to stay focused on what's important.
Self-Reflection
"Who looks outside dreams, who looks inside awakes." -- Carl Jung
One of the most important tools through this transition is your ability to glean meaning from the experience. This happens through self-reflection and attunement to your ongoing experience. Journaling, letter writing, meditation, and therapy all promote personal insight and self-understanding. Getting to know yourself, and what is happening internally frees you up to make better decisions, and to be more available on every level.
Vulnerability
"Vulnerability sounds like truth and feels like courage. Truth and courage aren't always comfortable, but they're never weakness." -- Brené Brown,
The end of a marriage comes with quite a bit of shame, which can lead you to hide your true feelings from others and even yourself. Exposing your darker side, and admitting you aren't perfect may seem counter-intuitive, but being vulnerable is the cornerstone of growth and true healing. When you fight your own experience, judge yourself for feeling hurt, or blame yourself for things that are out of your control you are creating unnecessary suffering for yourself. When you're brave enough to be in the darkness, you will see the light.
Intuition
"Intuition will tell the thinking mind where to look next." -- Jonas Salk
Self-trust can completely go out the window when your marriage ends because everything you thought was true is changing and up in the air. Your intuition can actually be a reliable source of information when you don't know which end is up. Intuition is under-rated and often written off as hokey and "out there", but coming back to what you truly feel and believe to be right will almost always lead you down an authentic and positive path.