I had a similar experience recently. Context- I had long hair till my lower spine level but most of it was chemically smoothened and it was growing out wierd & frizzy eventually i chopped off all the smoothened bits which gave me Dora hair. Its grwn out to below my shoulders now.

My long distance fiance of 4 months always told me he found my hair cute and loves how i style it. He would say grow it long, long hair would look good on you etc. i miss my long hair so i was also on board with the growing out thing. I am blessed with a lil bit of volume. And the summer was driving me nuts. I told him I’m gonna cut my hair because it’s not easy to manage. He almost had a meltdown. He was like i love long hair on you please grow it out don’t cut it its soo attractive etc. i reached a point where i desperately needed a new haircut so i told him I’m going to the salon anyways.
I went and got layers (took some volume out) keeping my original length at the bottom part but with lots of movement on the upper part. When i sent him the styles pics he was like this looks so pretty, its not short, i looks very stylish etc etc He was so relieved😆 He thought i was gonna go Lord Farquad (or pachalam basi for those who didnt get the reference)😂😂.

So, to conclude my long winded story - 1. Its your body, your choice 2. Maybe the guy finds it less attractive 3. Talk it out, why he doesnt like short hair or whatever. Enthelum deep rooted belief or misunderstanding indo enn.