Help! ADHD husband is regressing

Hi Everybody,

First of all, let me say thank you for being here. This forum is a life line that validates so much of my daily experience. I am non-ADHD and recently got married - my husband was diagnosed about a month after our wedding day, but he had already taken a psych test that strongly indicated he had ADHD about a month before the wedding. We've been together several years and, looking back, ADHD behaviours have been at the centre of most of our arguments - he could be forgetful, irresponsible, impulsive, rude/inappropriate and most of all come across as selfish because he would simply forget things I said and fail to fulfil promises time and time again. Wedding planning really pushed our relationship to the absolute brink it was the first time I realised that he couldn't do very simple tasks that anybody should be able to do (especially someone of his education). I started to suspect something was wrong because we would agree certain wedding-planning tasks together and split them between us then, weeks later, it would be like he didn't even remember we were planning a wedding.

Long story short, he was diagnosed and went on medication. The first few weeks of him on medication were GLORIOUS - he was listening to me, following up on things we had agreed and being attentive. He was also doing better at his work. I felt like the medication had quietened the ADHD symptoms and allowed his true self  - the person I had fallen in love with and still wanted to marry despite all our problems - to shine through. I breathed a sigh of relief.

Then, overnight it was like the meds just....STOPPED. Now, three months into him being on medication he has rebounded BIG TIME, he has quickly slipped right back to old habits. When I ask him to do something or tell him something important it goes in one ear and out the other, he has even started falling behind on work again and the few good organisational habits he started in the first few magical weeks of medication have disappeared. The worst part is that he simply does not LISTEN. I try to communicate with him but I think his mind just wanders off, he doesn't take in what I'm saying and/or immediately forgets it once I'm out of his eye line.

What's going on? Has anybody experienced this? I know he's taking the meds, is it truly possible they have just stopped working overnight? 

This time it hurts even more because I remember how amazing it was when the meds were working. We were both so happy but it feels like it's all been ripped away. Today, after a screaming match argument, I'm just feeling hopeless....any advice?