Hi :,) I am a 21F who just began dating a 23M. I’ve never been in a relationship before, let alone really more than 2 dates with someone. 
We started as FWB, and from that became the absolute best of friends, and a few weeks ago admitted we had feelings. He is such a wonderful person, and is doing everything he can to remind me that he adores me and wants to work through any difficulties we face and that he’s not gonna leave. 
But I have such a history of people not keeping their promises, and as soon as I left his place the other day, I couldn’t stop ruminating for hours just comparing myself to other girls he’s been with and just wanting to puke over how anxious I was to get close to someone and actually be in a relationship. 
I adore him wholeheartedly and I want to do this, because I know any relationship I begin will come with insecurity and learning to trust and work through my past trauma, and he is the most patient and loving person I’ve ever known to be able to do that alongside. 
Do you guys have any advice for a newbie romance? Or any good books/resources on relationship anxiety?