Jewelry. A topic close to my heart...

First of all, congratulations!

I can't tell you what you should feel, but I wouldn't enjoy that ring (and I am a HUGE sentimental sucker for all things heirloom...).

I think I would just be reminded of the ex every time I looked at it. And this is YOUR time.
You don't mention what kind of ring it is, but I would probably take the stone out and set it in a different setting, if that applies.

No matter if you are 18 or 80, you should enjoy your ring, your engagement, your planning, your shower, your gown, and your wedding....It's all fun and life is too short to worry about things you need not worry about.