Hi Carolyn,
First things first, I'm sorry to hear about your denial, and hope you can deal with the emotional baggage this journey brings.
That being said, I don't want to come across as judging, but as a concerned human being, and I hope you can see it that way also. I want to ask you some questions, and I really hope you can be critical with yourself, and put any emotion aside:
1. How sure are you that this relationship is bonafide on his side?
2. Are you with this young person because of any emotional attachments you had to your previous husband (also, I'm so sorry for your loss)?
3. Are there a deeply rooted emotional or even spiritual issues that you haven't addressed?
4. Have you thought about how this could impact your future?
I am sorry if I seem super direct in my questions. I know someone who's husband passed away and is chained to a terribly toxic relationship that many people tried to get them out of. We know that this person has a problem that's rooted within a desire to be loved and to get attention. When faced with these problems, we get desperate and often settle for less. I am just wondering if this MIGHT be similar to your case. Again, not confirming; just wondering.
Please, don't feel the need to answer my questions now (or ever), but I do advise that you go through a CRITICAL phase of self reflection, maybe with the help of a third party, and come up with answers for yourself.
If at the end of this reflective phase, you do decide to remain in this relationship; then I guess you could file for a CR1 after marrying.
Good luck Carolyn, and I wish you the best.