When you say have more Eman, what you are saying is that accept that in Islam it is ok for a father to tell his daughter to shut up, to get mad if she makes food he does not like. Eman does not require unmarried daughters to act like a chef in a restaurant; it requires them to do their best to make sure their parents are nourished.
I am not sure where and in what you see your solution to lie ... what is it that you're looking for? A change of mentality, change of family circumstances, or more explicitly, you turning your back on all that has been the source of grief for you and starting a new life? Regardless, for any of those matters to occur, it is your call, and your place to amend. You say you have tried all avenues, yet you feel unsatisfied ... well then that is just a matter of fate, and whether you would like to accept it, or keep referring to your family's attitude, which doesn't seem to change, the fact of the matter is you have to live with it, and you know that better than anyone.
Yes Islam is not what your family and brothers are doing, but what you're saying is quite a flawed logic too, because essentially Islam does not require anything of anyone. What we do is for ourselves. Islam does not require a wife to do anything for her husband either. If she wants, she can take the back seat, as far as being given her due for breastfeeding his child. Islam does not dictate that a woman become a chef in her husband's house either, or a cleaner to please him and his family. But if a woman wants her share of reward, to please her husband and to seek his pleasure, through which Allah's pleasure is sought, then a woman will embrace those things wholeheartedly. And it can't be more fulfilling in doing it for your own parents. They are the gateway to Jannah, the path to reward and the punishment too.
By Imaan I guess the sister was referring to a renewal of intentions. Undo those knots that have formed in your heart, those grudges that seem to stand in the way of accepting your fate. Yes, forty plus years is a long time to bear such a burden, but then forty plus years might also have taught you patience and perseverance, right? Renew your intentions, do it for Allah and ignore anything that happens in between. It is possible, these are not just mere words.