Anxiety and sadness will also arise. If this person is miserable or worried then this will feed into your emotions and these feelings will be shared. Worse, there could be the possibility of the relationship coming to an end, a thought which will swell within you and cause pain.
Love crystallises moments of euphoria, developing oceans of happiness in your heart and waves of worry, which remind you that this may be transient.
When you’re in love, transient feelings are always present. That’s why love hurts, even when it doesn’t.