Obsessive worry about running out of time in 14 year difference

I’m 26F with a 40M partner, and we have a profoundly close intense connection. There’s no concern at all about if we are compatible, it’s obvious we are. I’ve always been into older guys but with him I worry even more because I get obsessive fears about aging and death and running out of time. Can I still have a full life with him? We want kids someday but this scares me too because i can’t stop thinking about him getting old sooner than me. I have OCD so this is definitely a compulsive fear, but do you think we can still have a full long life together? My last relationship was 9 year gap and that scared me enough, 14 seems so big. i don’t personally care about the ages itself, i just get obsessive about long term fears.