I think it depends upon your motivation. It is a big change, that much you’ve already acknowledged. What is your reasoning for wanting to sell? No need to tell me or others, just to ask yourself. If it’s for the money, then ask yourself if it’s truly necessary.
Because it’s not just an object, it’s a place where you’ve stored memories, if you do sell, you will always have some degree of regret. The question is how much. Try to think ahead ten or even twenty years from now and how you see yourself looking back on the decision you made. Will you have wished that you had decided differently?
If it’s part of a much larger decision to, for example, move across the country, and signifies hanging on to something, then maybe you should part with it, and not look back about having made the decision to do so.
Finally, I may just be reading far too much into your question than I should. I do that sometimes.