Otoharo!
I can explain what it means to me, but this will be lengthy.
when one is in the head, one is hearing the chatter of the intellect including the ego. In the process I was taught to use, we chose rather to be conscious of ourselves as being in the heart area. (I susspect that there is another center rather than the heart itself that lies in our field of energy that is behind the heart.) With awareness of ourselves being other than in the mind, intellect, ego, (all of these), we can not be influenced; we can stay centered in our beingness only. Choices we make in this manner are true choices. Even though we always are free to change our choice at will.
Perhaps it is easier to say that will is accessed in this heart area, not thinking.
Now as you have related your question to romantic notions, that is something else again. You are referring to feelings. Our true feelings are ourselves. What we must discern is whether what we experience IS feelings or thoughts mascarading as feelings-- emotions. Emotions are not trustworthy whereas feelings are.
In other words there is no short cuts. It requires our accessing our true beingness when making life choices. Such as marriage.
finaltiy