Helping a girl out on what is OK sexually in a relationship (Severe sexual anxiety)

Hi guys! So just as a quick disclaimer, I'm in a healthy relationship with a loving and respecting partner, but I suffer from extreme anxiety when it comes to sex and intimacy of that kind and I was hoping that some people could give me their two cents on what is OK and healthy sexually in a committed relationship. Basically what are the right boundaries and where am I creating arbituary boundaries due to my anxiety? If you don't feel comfortable with anything that could be considered graphic, I would recommend you stop reading here.

Obviously I know consent is the number one thing, but how far does that extend? We don't ask our partners everytime we kiss them if it's OK to kiss them, because of course they can! How does that work with occasional intimate touching like butt squeezing, kissing a persons neck, fondling of breasts, or even running a hand down there? Saying no is never an issue in my relationship, but I always feel terrified that if there is any physical contact that is not necessarily wanted it is immediately a bad thing, like if we are showering together and he runs his hand down there to tease me a little bit. Or grabbing my butt sometimes when we kiss. Or a kind of intimate hug. Is this inheriently bad, or am I just overthinking any little touch because it often feels like other couples are more open with intimacy and I'm just so scared of it I think everything isn't OK.

My anxieties towards sex has gotten so bad it's since effected my sex drive and I have developed a deep fear of physical intimacy. I shy away from it scared that something will go wrong, but it's frustrating for both me and my partner because despite him being understanding and supporting we both have needs as adults. It gets draining where after a month of many no's (that are accepted, don't worry guys) and failed attempts I just feel like I'm the problem because I'm too scared of sex. And it doesn't help that he communicates his love best through intimacy (for his own reasons that I won't get through here but are valid and I respect that), but then I'm too terrified to face any kind of intimacy because I'm scared it's bad because I'm not necessarily "in the mood" or "wanting that", leaving us both drained emotionally.

I know some of what I say might sound like a red flag or a siren going off, but hear me out first guys. I'm just terrified of anything sexual at this point, and because of that it makes it hard to want anything intimate and not fear it. So, when he wants to show me he loves me by "pleasing me" or holding me intimately as a sign of trust of the many years we been together, I hate that I'm always scared of even trying, or getting so stressed over any small intimate touch that is spontanous and unplanned.

This is a topic we both constantly talk about: what is and isn't OK. And despite me hating the word we also talk about what is and isn't sexual assualt. But I'm still scared and I just wish someone would hold my hand and show me what are the right lines to follow.

I want to make my partner and me both happy, but I also don't want to ever push myself or make myself uncomfortable, and he agrees, because the point of intimacy in his eyes is making *ME* happy. So me stressing out about it and fearing it is the opposite of what he wants. He also never cares about being reciprocated, what makes him happy is making me happy, so it's just that much harder on me when I'm too terrified of even letting him try to make me happy because I'm worried it's inherently bad.

How do I overcome this anxiety guys? What do you consider OK in a relationship that is intimate and sexually active? Is every little touch bad or is there a definite line? How do I maintain a healthy, intimate relationship with my partner that wants to love me his own way, even if sometimes it scares me or makes me uncomfortable due to my anxiety?