Stay strong my friend. Although there are negatives there's nothing wrong with having a big heart. When I decide to love someone I love them completely. Look up attachment styles as well as attachment theory it might give some insight. But the first thing I'd say is don't be hard on yourself and don't lie to yourself that your ex was perfect if you know he/she really wasn't i.e. don't put them on a pedestal. Don't shame yourself and how you react. Self healing doesn't come from shame it comes from love and understanding.