Struggling with Trust Issues and Anxiety in a Healthy Relationship

Lately I've been struggling with intense trust issues and anxiety relating to my relationship. Past relationships have been so toxic, that despite the fact that I'm now in a healthy relationship I find myself questioning everything. I find myself wondering if my boyfriend still loves me, or if he is going to leave me for another girl with a better body even though he hasn't done anything to make me question these things. I'm so lost in my own anxieties and worries that I find myself thinking of worst case scenarios for everything. My relationship, future, job, etc.