touche, or maybe you’re a little “green”? I am guessing you are both relatively young and I would also ask how long you have been dating and how long you have been in taiwan.
if youre lonely, marriage will not be the solution, solve this problem first - this can multiply into a larger issue, ie, homesickness causing you to need to return home, but once married this is difficult and may cause you to feel trapped
also, from your OP, a marriage will not prove you are serious, solve this problem first, if the family do not think you are serious, then maybe this is projected upon them by your SO (hence why I used smokescreen).
As ab aside, if you are not happy to accept their traditions (which the OP implies), then you should consider how a 20-30 year marriage to that family will effect you in the long run. You will not change them by marrying their daughter, nor will you be a “white knight” riding in to save the princess from her “evil controlling father”.
am happy for you that you are ready to take this step, but it is not a step that should be taken lightly, nor is it the be all and end all of any relationship issues.
Cross cultural marriages and distance relationships (with your family/friends/nation) are difficult, I am just saying that more thought may need to be put in.