It looks like there is an identity clash here: you only identify as ethnically and culturally Jewish, and a big part of your father’s identity as a Jewish parent is that his children continue on the religious aspects of being Jewish. While you could potentially accommodate his needs by mindlessly following the traditions that feel empty to you, it is clear from what you said that you have had enough of that in your life and are done with pleasing your father, no matter how much you love and respect him, and no matter how much you depend on him financially. This quality of finding your own way, of being strong enough to face the headwinds without breaking is likely something your father values and respects in you, even while regretting that it manifested in the way it has, standing up to him on the topic that is supremely important to his identity as a Jew and a father.
My guess is this is not about you at all, it is about him feeling like he failed to achieved one oh his most cherished goals, despite doing his best. Imagine being in his situation, imagine how much it would hurt, 20-30 years down the road, to realize that all the labor of love was for naught, at least in your mind. Once you feel the enormity of your father’s pain like it is your own, you may notice that his implicit threats to cut you off come from the place of hurt, it is him trying to reconcile what he values with what he sees.
It looks like you want to have a good and healthy relationship with your father, given that he is intelligent, generally open-minded, and really loves you and cares about you. If he were able to accept that you going your own way does not reflect badly on him, is not his failure, but just the way life is sometimes, then it would be easier for him to accept you as you are. What might help him feel less like a failure in this one important area of his life? What can you do to help him get there? Think of various options, be creative. Would a talk with his rabbi be helpful? Your father is much more likely to listen to someone like that than to you. Would you acknowledging his feelings, and empathizing with his need to see his children continue the religious, and not just the cultural traditions of Judaism help soothe his pain? It may be worth discussing what he wants to happen at this point in time, given your current state of mind. Does he really want you to go through the motions with no feelings behind them? Would you being his puppet really fulfill his need? If he says something like “I wish you could just believe the truth of …”, what kind of a reply would appeal to both his heart and his mind, without compromising your own beliefs? What else does he value in you, beyond being a good Jew? How do some of these traits clash with your ability to be what he wants you to be religion-wise? Would he want you to give up being someone that he is proud of for the sake of being a good reform Jew? Think a bit more about being in his place, run the model of your father in your mind, and see what it tells you about meeting his needs without compromising your own.
You and your father are both smart, open-minded and accepting in many areas, so there is a good chance that with some mutual acceptance, understanding and compassion you can get to the place where both of you, while not getting everything you wanted, are able to have a good and healthy relationship. Imagine that you got there. What would this relationship look like? Then work backwards and see if you map out the steps of getting there. Odds are, you would grow as a person in the process, even if you are not 100% successful, which is not the worst outcome possible. Good luck!
It looks like there is an identity clash here: you only identify as ethnically and culturally Jewish, and a big part of your father’s identity as a Jewish parent is that his children continue on the religious aspects of being Jewish. While you could potentially accommodate his needs by mindlessly following the traditions that feel empty to you, it is clear from what you said that you have had enough of that in your life and are done with pleasing your father, no matter how much you love and respect him, and no matter how much you depend on him financially. This quality of finding your own way, of being strong enough to face the headwinds without breaking is likely something your father values and respects in you, even while regretting that it manifested in the way it has, standing up to him on the topic that is supremely important to his identity as a Jew and a father.
My guess is this is not about you at all, it is about him feeling like he failed to achieved one oh his most cherished goals, despite doing his best. Imagine being in his situation, imagine how much it would hurt, 20-30 years down the road, to realize that all the labor of love was for naught, at least in your mind. Once you feel the enormity of your father’s pain like it is your own, you may notice that his implicit threats to cut you off come from the place of hurt, it is him trying to reconcile what he values with what he sees.
It looks like you want to have a good and healthy relationship with your father, given that he is intelligent, generally open-minded, and really loves you and cares about you. If he were able to accept that you going your own way does not reflect badly on him, is not his failure, but just the way life is sometimes, then it would be easier for him to accept you as you are. What might help him feel less like a failure in this one important area of his life? What can you do to help him get there? Think of various options, be creative. Would a talk with his rabbi be helpful? Your father is much more likely to listen to someone like that than to you. Would you acknowledging his feelings, and empathizing with his need to see his children continue the religious, and not just the cultural traditions of Judaism help soothe his pain? It may be worth discussing what he wants to happen at this point in time, given your current state of mind. Does he really want you to go through the motions with no feelings behind them? Would you being his puppet really fulfill his need? If he says something like “I wish you could just believe the truth of …”, what kind of a reply would appeal to both his heart and his mind, without compromising your own beliefs? What else does he value in you, beyond being a good Jew? How do some of these traits clash with your ability to be what he wants you to be religion-wise? Would he want you to give up being someone that he is proud of for the sake of being a good reform Jew? Think a bit more about being in his place, run the model of your father in your mind, and see what it tells you about meeting his needs without compromising your own.
You and your father are both smart, open-minded and accepting in many areas, so there is a good chance that with some mutual acceptance, understanding and compassion you can get to the place where both of you, while not getting everything you wanted, are able to have a good and healthy relationship. Imagine that you got there. What would this relationship look like? Then work backwards and see if you map out the steps of getting there. Odds are, you would grow as a person in the process, even if you are not 100% successful, which is not the worst outcome possible. Good luck!