Your husband died in a car accident before marriage, which is his destiny. Although it's bad luck for you, it's a small disaster, and the bad luck has passed. After all, if it happens again soon after your marriage, it will be a catastrophe. For me, getting married in the future means getting married. Unlike in ancient times, it's not your fault if you are engaged, even if you have established a relationship and are not married. If you get married, it's hard to say.
Anyway, you didn't kill him. If you want to kill him, you have to get married, and the gap between feelings will be over. The result of signing the book is the result at that time, which is changing at any time. If not, try to avoid it.