Behavior ends relationship

Hi this is my first post here. I was diagnosed with ADHD about 3 years ago and was on Adderoll XR since then but have struggled to take it regularly and haven't taken it at all since last fall. Im gay and have been in a committed relationship the last 9 years. I work for myself as a contractor which I believe is very detrimental to me with ADHD. I struggle to finish projects and always have clients angry with me even though they love my creativity and are usually very happy with the project itself just unhappy with my inability to schedule and finish the most minor of details. I haven't been seeing my therapist and have admittedly let my treatment slip into the toilet. I had used my partners credit cards without his knowledge and amassed about 10,000 in bills on 2 cards, 99% of the expenses were related to my work and I thought I could pay them off without his knowing what I had done, a terrible mistake and fatal to our relationship. I do not have this behavior issue in other areas , I do not steal from anyone, although my partner says I have stolen from him by doing this, my brain doesn't process it like that but I bet everyone else sees it like he does. I am very sorry for what I've done and especially that it has ruined our relationship, he is such a great person and has had to deal with me and my adhd problems throughout our relationship. Most of my issues with ADHD manifest themselves in my financial life. I struggle to pay bills, I lost my health insurance last fall about the time i stopped my medication and quit going to my doctor. I know i need to get back to the doctor and get back on meds, they did help me a lot when i took them as directed. I don't know what I hoped to accomplish by posting here, I wondered if anyone else had such bad behavior, I feel so terrible about what I've done. Amazingly most all of our friends have contacted me to to tell me they love me and that they will help anyway they can. Well I guess I need to get packing, I have to move out of our house this week while he is on vacation, how could I have done this to someone who cared so much for me? I don't blame him for having to end this, why should he sacrifice his happiness while I can't get myself together to be an equal partner in the relationship. He says that breaking the trust we had is what did the damage and I can see that. Has anyone else here had similar problems, did my ADHD cause me to do something so dishonest and hurtful?