If you haven't already, communicate with your partner about your feelings, especially from previous experiences and the fears you have of someone harming your partner.
Whoever hurt you or your partner in the past cannot hurt you or your partner again. The risk of being attacked will always be there but if you are together in public, the risk is significantly lessened than if one of you were to walk alone in the dark. This goes for anyone, regardless of identity. It's normal to feel protective of your partner but when protectiveness crosses over into the line of possessiveness, you need to step back and have alone time to carefully re-evaluate yourself.
If you don't already, learn to trust your partner and have coping methods in place to fight against the anxiety. If thoughts crop up, try not to feed into it as it will make it worse. Distractions can help and expressing yourself also helps to lessen the severity. Keeping it bottled up and festering into it will only make matters worse (not implying you are, just speaking from personal experiences).
Hope this helps, I wish you luck!
