If this is the only issue in your relationship, you need to have a logical look at the situation. Yes, you have an age gap, but there are horror stories and happy endings in all types of relationships.
There is an age gap of less than a month between me and my husband - he is slightly older and for nearly 3 weeks a year, I can wind him up about how old he is. We've been together 30 years.
This year, he nearly became a widower at 48. I was critically ill but recovered (not covid!). In the space of a few hours he went from me being under the weather to the hospital having 24 hours to save my life. Had I died, he would been considered to be widowed very young, yet there was no age gap at all - it would have just been terrible luck.
Instead, he's stuck with me because the NHS was amazing!
My mum is 77 - she has been widowed for 25 years. My Dad was only 5 years older than her. Not a huge gap at all, yet see how much longer lived she is.
None of us know what the future holds. As a race, we don't have a fixed age span. It isn't written in stone that your partner will die 14 years before you because that is the age gap.
This year has shown me that I made the best decision of my life when I married my husband. He's loving, caring, supportive and good to the core. We've had hard times, difficult times even, but my life is so much better for having him in it.
Does my mum regret marrying my dad, because she was widowed so early - hell no! She had a good marriage and the strength to carry on.
You could be sitting at home at 86, celebrating his 100th birthday! Life isn't straight forward - that's what makes it interesting. Look at your relationship. Do you love him? Do you want to be with him? Is there anything stopping you? Is there anything you need to resolve that can be resolved - an age gap can't be changed, but it isn't a death sentence!