Not knowing either one of you and basing this off of what you said, it sounds to me like the love is one sided. Regardless whether you have ADHD or not, you deserve to be with someone that doesn’t ignore you. There is no excuse to go that long without communication unless she is unaware of your feelings, and believes you two are just friends? I go long periods of time without talking to my friends, but never ignore them.
I have ADHD and often forget to respond to my boyfriend if I am at work, or in the middle of something. BUT, I don’t go more than a day. I will think about him and pick up my phone to see how his day is going and that is when I generally realize I hadn’t responded to him, or checked my phone when I heard the notification go off. He knows this about me, and knows how easily I get side tracked and forget. If it is important he will text again, or call, if I don’t respond in a certain amount of time. Otherwise he knows I will respond once I remember to check my phone.
If she is aware of your feelings, and does what you have described, then myself, I would not respond to her next time she came around. That is neither a friend, nor someone that cares about you. There is someone out there that will appreciate you and your feelings,