Not psycho, but clingy yeh. And you're not alone.
Well, what it comes down to is self esteem and self worth, you need to love yourself enough to let go if things aren't working out. Bear in mind that no relationship is permanent, either via problems or when we die we eventually let go. Be in relationship for love and to solve problems for as long as there is the will to do so, but if that will is gone and your partner wants to leave, let them go.
Don't cry, don't regret and don't blame
Weak find the whip, willing find freedom
Towards the sun, carry your name
In warm hands you are given
Ask the wind for the way
Uncertainty's gone, your path will unravel
Accept all as it is and do not blame
God or the Devil
~Born to Live - Mavrik~