Trust issues with my bf..

So my boyfriend and I dated for six months back in 2019, we broke up January 2020, stayed friends and talked a lot after that and in July 2021 we got back together and have been going strong since. He is honestly my best friend but I feel like I would could be more comfortable and secure with him and maybe I have trust issues. In Jan 2020 we broke up because he wasn’t ready for a relationship yet and he felt like his ex messed him up too much. It wasn’t a bad breakup but I honestly felt so sad about it because of how easily he was able to walk away after saying how much he loved me and cared about me and then it was like a snap and a total different story. Now its 2022 and so much time has passed since then and I honestly kicked some booty as a single lady and I grew to love myself and love being single. and then we got back together and he’s a totally different guy. He’s assertive he expresses his feelings he is going out of his way left and right to make sure I am okay and to be next to me always, we are planning our future together and we don’t ever make any decisions without eachother, like this is a great relationship. So why do I still have trust issues from when we dated before? Obviously he’s different now, but I still have this fear that if he was able to leave so suddenly after saying how much he loved me, that it will be the same this time around, despite the fact that he is so different and we are so different. I don’t really know how to snap out if this and I don’t want to talk to him about this because I think it would make him so sad to know I was still hurt over that.