Chevca, I'm going to be totally technical with you. First of all... If a relationship ends passionately... it is the emotional equivalent of INDIGESTION.
In the case of your ex, Meghan, who went back to her ex, Who ever ended it... there were still things left to say and do for closure.
Sorry to say but the greatest likelihood is that you were the perfect canvas for her to offset her INDIGESTION with joy and fun... BUT that's just a bandaid. The underlying need to clear the EMOTIONAL CONSTIPATION is still foremost... THATS why she went back to her ex... it has nothing to do with how much FUN she had with you.
THAT is also why people bring baggage from one relationship to another... AND WHY they look for someone who is JUST LIKE THEIR EX who is JUST LIKE THEIR EX who is just like their MOM/DAD.
You are now... likely to perpetuate that same cycle.
Just make sure that every cycle... is complete and at peace before starting another cycle. In your case... it may mean waiting long enough for that desire to FIND SOMEONE TO REPLACE your ex totally goes away... then you'll find the right partner for the RIGHT reasons.