How do I stop my relationship anxiety and paranoia?

Hi all, I've been with my amazing boyfriend for 2 years, things have been amazing and we really took big steps in our relationship. I've suffered with anxiety for over 10 years and I guess now it's carried with me into the relationship. I have a constant worry in me head that he's finding something better and being sneaky (even though my heart tells me I have a faithful and genuine man). We did have a issue a few months ago where he was messaging another woman, although it wasn't sexual or anything he was using pet names which I found disrespectful, I confronted him and we spoke of it and sorted things out. About a week ago someone called him (number wasn't saved) and he quickly declined the call, I didn't question it then as we were with my family but I did bring it up later and he said it was his best friend. A few days ago his friend called him and it was a completely different number, I did check the call log and the number from a week ago wasn't there anymore (I know I shouldn't be checking his phone, there is nothing bad to find apart from messages to a female colleague where he talks about work issues that I have no idea about). So I asked if he felt like he couldn't talk to me and be open to which he said he can its just he doesn't want to make me sad. I also asked about the girl he texted previously and he said he'd blocked her because I didn't like it. I guess I just want to learn how to be more easy going and laid back because I know he's a sweetheart and wouldn't intentionally hurt me. I trust him completely, more than I trust myself and i do not want to lose him but the anxiety and paranoia feels like i'll be pushing him away. I think he doesn't tell me things because he's scared of my reaction and he knows I'm an overthinker. Any kind advice will be appreciated.
How do I stop my relationship anxiety and paranoia?
Add Opinion