Telling my husband

I've been referred for an assessment by my GP and haven't told anyone else. I'm in my thirties and have been married for nearly a decade. 

Last month I saw a post on social media about female autistic traits and surprisingly, I could relate to every one of them. I started researching and spoke to someone at NAS and took the AQ test they advised. I scored 37. It was like a slow dawning, where all my sensory quirks and social anxieties and list-making connected into something larger. Before that, I wouldn't have believed I was autistic. Last week I realised that some of my behaviours could be labelled as stimming - (I've always had these but previously thought were part of my overall 'weirdness'). 

I haven't told my husband. I think that if I said I might be autistic, he wouldn't believe me (I struggled to believe it at first). He's not unkind or cruel. 

I'm worried about telling him, in case I am assessed and I don't get an autism diagnosis. Then, I'd have to accept that I am just weird and I'd feel embarrassed at exposing a part of me that I've worked my whole life to keep hidden. 

I'm assuming they'll want to speak to him at the assessment, so I've got to tell him at some point. 

Any advice on how to tell a partner or family member about a referral?