If you wouldn't feel comfortable inviting them to a dinner party, don't invite them to your shower.
If it's been more than a year since you've socialized, don't invite them to your shower.
There are a couple of exceptions to both of these, but neither apply in your case. Don't invite them.
People do love buying baby gifts, though, so be prepared with your response when they ask what you need or where you're registered. Also be prepared for the "when is your shower" questions. If someone who won't be invited asks, it's good to have a plan to handle it.