A warm heart

Why do people need a partner to survive? Why don't they live of just by themselves?Is it that necessary to love someone?Why do people want to love and be loved?How is it that they want to let go of all other feelings other than love? What's so important about it?They say love makes their heart warm or whatever,is it that necessary to feel warm in your heart?Why do they waste almost half of their precious time thinking about finding love or sustaining a good relationship with their alleged loved ones?Why do they need do that?Why is it that they always try to beat others in any way they can so that they may reach the top but gives up everything for that person whom he allegedly love,with whom he/she has no blood connections?Why is it so important to love or be loved?Why do they need a so called warm heart?