OCD VS Autism and BPD ft bipolar disorder
Before we did Autism vs OCPD differences/overlaps which is located here https://www.7cups.com/forum/personalitydisorders/General_2436/OCPDvsAutism_340746/ ( in case you can not find it), and we also did another OCD vs OCPD which is located here https://www.7cups.com/forum/personalitydisorders/General_2436/OCDVSOCPD_340637/ ( in case you could not find it.)
I wanted to take more time and break things down a little further and share imagery of the differences of OCD/Autism and BPD featuring bipolar disorder. It is always important to know the differences, and the overlaps which is why it is more than okay to take notes and provide them to a professional, but not self-diagnose. Here are the images: 
This one above is the differences between OCD vs Bipolar disorder and known ways to assist with each of these disorders. 
This one above is the circle diagram of the differences of not only OCD vs Autism, but Autism vs BPD and BPD vs Autism. It is always important to notice the differences and the overlaps, because sometimes the overlaps can make it hard to diagnose. Which is why taking notes is always okay, and taking them to a professional however self-diagnosis is not because there are too many overlaps.
What are ways a Personality Disorder is formed? The way a Personality Disorder is formed is three things Biological circumstances, Social &Environmental circumstances (these two are combined) and Psychological circumstances!
I hope that narrowing things down, and deepening the understanding is helpful <3