Being with a secure partner not helping

I’ve been dating my bf around 6 months (official the last 3). He’s wonderful, communicative, and very secure. We’ve met each other’s parents and have trips planned for later this summer (all signs I should take as reassuring). However, the family thing was recent and taking a lot of big steps has made me more anxious than ever about my bf ending things. Small things like him talking about his friend ending a relationship cause a pit in my stomach. We also haven’t said I love you yet, which might be the source of a lot of this anxiety. My bf has said he’s really happy with how things are going and other reassuring things, but I cannot shake my anxiety. Part of me expected finding a secure partner to make the anxious tendencies disappear but that has not been the case. Do I just give it time? Talk to my bf about it? Would love any advice or hearing about others experience. This is my first serious relationship so everything is unchartered territory for me.