Hi,
I think that one of the first reason, why so many relationships fail is because people don't know themselves. It is very important to first know yourself, before starting a serious relationship.
If you know who you are and if you know what you want, you will be able to know who fits into your life, and who won't manage to cope with your lifestyle. For that reason you first of all need to know your inner true wishes. Because no matter how much you ignore your true self (maybe because you are too busy with the quarrel of everyday life) your true self will always push you towards your true wishes. Soon or later you will find yourself running after things, you are inwardly longing for.
And if you don't know what your desired lifestyle is, your current relationship will fail, because you and your partner will drift your lives apart. Everybody is torn towards the direction he/she is inwardly longing for in his/her true self...
so, it will heal much pain concerning relationships if you first of all ask yourself WHAT YOU WANT in life, before picking a person for a long term relationship, if you want to be seriously happy.
kind regards and all the best,
Anna Emilie.