ADHD partner wants to leave

Hi! I am new to this community!

My husband has recently been diagnosed with ADHD and everything has clicked into place. We have a typical ADHD marriage with all the issues. Now we know this I have been reading all the articles and books, listening to all the podcasts, joined a support group and have been looking for a couples therapist.

It seems like it isn't enough for him though. We have talked about separation (I instigated it) but now I understand the ADHD I no longer want this. One day we are great, super happy, and be recognises that our issues revolve around his ADHD, and the next he is saying I have 'worn him down' with our parent/child dynamic and our relationship is toxic and he wants to leave. It is so confusing for me. I am trying to hard to save this, for the sake of the love that we share but also our 2 year old.

How can I get through this?