If you find your world revolving around the other person, if their mood affects your mood for days, and if you find yourself anxious every time you are without them, then you are most probably too attached to that person.  When you are too attached to someone, you can’t imagine being away from them for even a small period of time and you get negative thoughts when you are apart. This is a sign of an unhealthy attachment style that can be detrimental to your mental health.