Not exactly the same situation but I split with my ex because it had felt for a couple of years that I was not his priority. I had asked, asked and asked again to go places, do things together, spend meaningful time together but he was always too tired, too busy with work, not now but maybe next week (never happened next week) other family members needed him (I needed him!)
When I broke up with him, he started saying "Don't say that. We can go to X, we can do Y, I'll do Z..." - all the things I had been asking for repeatedly. Luckily for me, it just made me angry. "So you could do all those things, you just chose not to, you chose not to inconvenience yourself for my happiness, when I was constantly inconveniencing myself for yours?"
Keep hold of your anger. You are doing the right thing. You will miss him and have regrets, but keep re-reading these threads and stay strong.
N.B. I met a lovely man in my 40s and I am 100% his top priority. Not saying it's perfect but we both make compromises and consider the other person. It's not one way traffic.