Welcome to PC.

Sounds like this is the place for you. Though, I'm sorry for your troubles and I'm sorry you're hurting.

Do you have a therapist or maybe have someone you can confide in other than your partner? This is a difficult endeavor to go about on your own but it's not impossible.

This is a good place to begin learning more about your own situation and maybe how to go about getting through these insecurities.
What I know about my own insecurities: They won't go away on their own. I have to face them and figure out the root cause behind what they've become. Then, sometimes, I've had to make peace with them.
This site will be here as you move towards recovery and will be here to offer you all the support we can.