I just thought about this question because my crush (who will probably never like me back) told me "you've changed" and "I don't even know you anymore" because lately I've been more immature and comfortable around . I wonder it was meant as a good thing or bad thing
But yeah, would you change for the one you love? Or should he/ she change for you?
Yes. Everyone is the way they are, but there's always room for a little bit of change (obviously nothing drastic otherwise they can keep it ). I'd expect them to do the same for me.
No. Everybody changes over time (especially if you're in a long-term relationship), but those out of the blue changes never last long. If you want to change something do it for yourself.