Angie, you are gorgeous in every photo! Such luminous skin, such bright eyes, such lovely colouring, and such a fantastic smile. (Not to mention, such cute companions at all ages and stages!)
BUT...I have to admit, I agree with your mother. Now, this may admittedly be the influence of my own mother, who similarly, always preferred me with short hair and never made any bones about telling me so!
Our face shapes/ bone structures are quite different. But one thing I think we may have in common is that longer hair tends to "overwhelm" us somehow, taking attention away from our features. You have gorgeous hair. I also did, as a teen and young adult, and when I had it longer, my friends tended to want me to keep it because it was pretty in itself. But they weren't seeing the whole aesthetic picture -- how it unbalanced me, stole the attention and almost weighed me down. I think something similar might be the case for you.