Pain needs to be processed. That doesn't mean you 'get over' whatever happened, it means that you can healthily revive. Remember that in the end pain can turn into power.
Being in a negative, depressed state of mind for a long time can lead to unhealthy actions or other emotions. Sometimes people don't mean to take it out on those close to them, have a healthy outlet. Pain needs to be processed, it shouldn't be held, the burden needs to be set down. It doesn't mean its not there but it's the first step to having a lighter load while dealing with grief.
1) Process the pain, it's ok to cry. Let it out, talk to the wind, when exercising give it your all. Watch helpful movies, read good books. Some that can help are Gifts From the Sea by Anne Lindbergh and The Untethered Soul by Micheal Singer.
2) Talk to someone who won't feel burdened by it. Talk to a mentor or therapist who can help you process it.
3) Let go of 'things' in your life. If 'stuff' you have doesn't bring you joy, let it go. If you need to forgive, try if you need to apologize, do it - often.
When you let the pain out, your burden will be lighter. It doesn't mean you will forget, but you can begin to heal or keep the cherished memories. The process will take time but the outcome will be healing. If you want to talk, or need help processing grief, here are some good resources:
Sign up for Coaching
The Pain of Progress
Why You Need Both Order and Chaos in Your Life
My Worst, Loneliest Christmas
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