sometimes we don't do word-to-word traslation... the sentace may mean "i miss you so much that i can't even breathe" 到 means "to some extent" in this sentance, so 想 and 到 are two words that both have its meaning in the sentance.

好想你, 想到不能呼吸.- I am thinking of you, reaching to the point of disable to breath. 想 is a continuation from the previous words (好想你),.....到, reaching the point of..... 我好想你, 想到愿意相信. I am thinking of you until the willingness of believing ( no such expression in chinese). Application: 我好想你, 想到生病了...until I got sick.

oh , i think that means till or until

想表示动作，想到＝想＋以至于in order to＝结果是come out I hope this explanation is effective

「氫氧化得瑟」の答えはとてもいい