First off, when I started riding the tandem, it took about a thousand miles before it felt "normal" and didn't just feel totally weird.
Secondly, it is a different situation from riding single bikes for several reasons. It's kind of like the difference between driving a sports car around town and driving a semi. You CAN drive the semi around town, but it obviously works better on the open road. The tandem is more awkward to start and stop, accelerates less quickly, requires more room to make turns, and comes with double the responsibility.
My advice is go somewhere with less-busy roads or wide-open trails and just make an opportunity to ride it more where it IS easy. Not once or twice, but a lot. Get out and have fun on the thing where it IS fun for both of you. That may or may not change the situation on busy roads, etc- no guarantees there!


One of the local bike club rides involves a ride down White Rock Creek Trail. This is a paved trail, but it's not very wide, has a fair number of other cyclists and pedestrians, and the bike club rides it at about 20 mph at night. There's a couple that rides a tandem on that ride. Meanwhile, I've got about 25,000 miles of tandem experience now, and that is the last place I would want to take MY tandem. So I enjoy riding it, but don't want to ride it everywhere I go, either.