This book is quite good, https://www.amazon.com/Marriage-Relationships-Aspergers-Syndrome-Spectrum-ebook/dp/B00Y94ZTEA . It's strange that he's gone like this, I would've expected the aspie to be more likely to retreat. Definitely recommend counseling if you can. Need someone who specializes in ND though
Here is one book I found on Amazon, and this might be the workbook you saw. I don't know anything about either book other than what Amazon says, so look through them to make sure they're right for you. I'd also suggest exploring the Autistic Women and Nonbinary Network
So, I'm not sure which specific ones I was referring to, but I can pass along a few links that might be helpful.
AANE: Romantic Relationships with Aspergers/Autism (The speaker on this one, Eva Mendes, wrote the book Marriage & Lasting Relationships with Aspergers, which is quite good. It goes into the same topics in more detail).
AANE: Communication Challenges in Neurodiverse Partnerships
AANE: Viewing Marriange & Long Term Relationships Through an Aspergers Lens
If you are interested in less formal discussions, the Youtube channel Aspergers from the Inside has some good content on relationships. Paul has a special interest in emotional intelligence and works as a life coach.
Another less formal discussion is the video by Purple Ella. She's been married for 18 years and shares some things she's learned over the years.
That's all I have for now. All the best!