What happened with the father of your dc? Did he leave you, or vv?
I agree with pps that you may not be cut out for this sort of relationship. Your reaction to 'being dumped' for a better offer from 'a family member' who in another post turns out to be his dd (from his first marriage?) isn't really fair to him, especially when he invited you to come as well. That's not being dumped and he could hardly turn down his dd, who must have known his late wife, on the anniversary of her death.
You've only been with him for a year. It's stiil early days for you two, compared with his previous partners. You don't live together and you have baggage of your own, with dc from a former DP, which gets in the way of your new relationship. You can't put him first, either, for understandable reasons, but from his pov he might be pacing himself, holding back a little from making you his absolutely number one priority, because you can't do that for him. He has a lot of other people in his life whose feelings he has to consider as well as yours. It's not surprising that you don't feel as if you're on the same page as him.
It's really up to you, whether the good times are good enough to make it worth going with the flow and overlooking small things that he is bound to do or say without any intention of hurting or belittling you.
I can see that the fact that his former wife Is no longer alive adds an extra complication. But I'm wondering if she were still here, with dcs leading to a step situation, blended family issues, would that also be a struggle for you?
You may have taken on more than you can cope with, or it could be a chance to learn and grow as a person. Only you can tell.