Do you have trouble with the fact that you are getting older but your beloved stays (very) young?

I'm thankful to have come across this community today, because I can't really talk to anyone else with these thoughts that could relate. Thanks for that.

Well, the title question actually says it all, and it's causing me problems. Whereas, not really problems, more like headaches.

When I was 11, I fell in love with my f/o. These feelings lasted for a whole 10 years. Even my mother, the only one who expressed something like understanding for my feelings, affirmed that he (meaning he's m, I'm f) was probably my youth love.

The manga/anime he was in ended at some point, and from then on there was no more canon "input" for me. The big infatuation feeling then diminished within a few more years, until I found a new crush. Still, he never disappeared from my life; the pictures I had of him on the walls became fewer, but remained.

The series, from which he comes, is not very popular. Much of it did not make it to Europe, and at least in the past you could not easily access the original Japanese manga. Also the series disappeared from YouTube, because of copyright.

Today it's different, and I've started to get more involved with the series and him again, also because of the new "input" for me, which I now have access to thanks to a hoster.

The feelings are back. Different than before, but I accept that, on the whole, I just can't imagine my life without him.

The crux of the matter: Even if he seems visually a bit more mature and has very serious sides to him, he is and remains 13 years old according to the information. Original exist, unfortunately, only 2 pictures that show him grown up. So all I have, with which I mainly dream, are the series and the manga, where he is just very young. And I'm not 11 anymore, not for a long time.

It feels "wrong." The two crushs I've had in the last 10 years after him were 20+ from age. And now I'm going back to the roots... And can't really let go because of that thought (I'm not into kids; in RL I don't even like them...).

The only thing I came up with as a "solution" to this is to imagine the sexual aspect only with his older self. But that is somehow also a bit difficult, because as I said, there is no information about this self (except for said 2 pictures).
I'm also toying with the idea of drawing a sort of spin-off, in which he lives a family life as an adult with my OC created for the series. With it I would finally see him in his adult form further, if it is already canonically denied to me.

Is anyone here perhaps also like that or has anyone experienced something similar? How do you deal with it? Basically, I try to realize that the thoughts are free and he is "offscreen" also an adult already, but...