Using the past for your benifit

[Insightful27]

When something bad happens in the past that we had control over, isn't it worth it to ruminate on it? That way in the future there will be a phycological pain attached to it so that its not repeated? In that sense you could use the past as a means to make the future better.
 

[susanyzm]

Yes, I agree. 

Ruminate on it from a positive intention: "What have I learned about myself? What have I learned about life?" Then move on with life.

What doesn't help is to ruminate from a negative intention: "Why did it happen to me? I wish I could have done something to make it better." 

Everything is a treasure in disguise.