People with attachment disorders lack the ability to self-soothe. Instead, they look to another person for reassurance. The panic you describe is very real because on some level, the issue is perceived as a psychological struggle to survive. All of us get pretty panicky if we’re facing the psychological equivalent of falling off a cliff or getting run over by a truck. Also, since wounding from attachment disorders happens at a very early age, words of reassurance from the other person often aren’t as helpful as non-verbal things such as voice tone, facial expression, gestures and actions.

You might want to consider getting some therapy. Right now it probably seems as if things were more stable in your relationship everything would be OK. However, working through your issues in therapy would help you get stronger within yourself, which would leave you less vulnerable to the inevitable ups and downs that occur in any relationship.