Why? Heart or mind??

Today i find myself in a precarious situation trying to answer one of those questions that do not have answers. I really do not understand human beings (of course me included). Why do we choose to follow our heads when our hearts say something different? First of all, which of the two organs is to be trusted? Is is the heart which gets so emotional or is it the mind which helps in over thinking simple situations? I have often found myself in situations where my heart tells me that something is right but my head (my small head) tells me that i should not follow that route. My mind really leads me into being proud and stubborn. While these characteristics are not so bad, at times they make me loose sight of the real life. On the other hand, the heart usually tells me to go for what i want, at the time i want it. My heart tells me that i should be with someone when i feel like it but my mind tells me that i should hold out a little bit more. Now, these crossroads are so many. And i continue to wonder, is it the heart or is the mind that is should use in order to live life perfectly. I still question me and i seek answers. Is it the heart or is it the mind??
Kisses n love ya.