I’m not an expert by any means and everything I’m about to say is just my opinion.
for 99% of relationships, the initial “spark” is the physical attraction between two people. Looks basically help get ur foot in the door, it’s not the end all be all. As men, we are heavily looks biased. For many women (Mid 20s and above), u need to meet a minimum looks threshold, then other things come into play: your personality, confidence, status, etc.
As women start to fall in love with their partner, looks take less of priority. Of course you can’t just assume you can now become a slob and not have good hygiene and not take care of yourself.
there are exceptions to everything in life however and there are some women who are heavily looks biased. But that raises the question, did she love you bc of your looks only? If the answer is yes, that relationship wasn’t meant to last anyway. We all get older and less attractive as we age so it’s very unreasonable to expect someone to retain their looks as they get older.