My wife of 25+ years walked out on me and my 2 youngest boys (11 and 13 at the time). I know what you're gong thru. Sorry you're going thru this. Don't blame yourself. Two people are involved in every marriage and breakup.
Not sure if there's a reason or purpose but it will get better. It definitely did for me.
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The Lord is merciful and gracious, slow to anger and abounding in steadfast love. - Psalm 103:8
I am a cyclist. I am not the fastest or the fittest. But I will get to where I'm going with a smile on my face.