Recommendations to empathise with autistic boyfriend


I would like some recommendations (e.g. reading materials) for me (a non-autistic person) to be able to empathise better with my boyfriend. 

I'm dating a very lovely (probably, but never diagnosed) autistic man.  He cares very deeply about me, but on some occasions this doesn't come across in his actions as he's wired a little differently.  There are a lot of small examples, such as leaving a cafe table when he's done, despite the fact that I still haven't finished my coffee, or not being very good at knowing what to do if I'm ill.  In these situations, I know on an intellectual level that he does care, but it can be difficult not to have a emotional reaction in the opposite direction.  

He's working on trying to be more aware of my feelings, but I also need to do the same in return, in particular understanding him better and not feeling so offended when these things happen, but also how I can change my actions to make it easier for him. 

Has anyone got any recommendations to help me here?  I was imagining that someone might have a book that they found helpful, but I'm happy to look at something in whatever form - blog post, documentary, magazine article, TED talk, TV series, or your own comments and recommendations. 

Thanks in advance.