Mexican Petunia - Ut Oh

Umm, this came from Sue's garden.  It's such a cute, tiny little plant with such delicate pretty purple flowers.  I didn't know it was a very invasive, aggressive monster.  At least, if you read about Mexican Petunias on the Internet, there are a lot of "WARNINGS" about the plant.

I'm wondering if I shouldn't dig it up.  I'm sure a more seasoned gardener would do a better job of maintaining this plant, but I'm a newbie with gardening and I feel as though someone dropped a monster in the yard!

A pretty one though.

It's sometimes referred to as Purple Showers.  Funny thing is, if I'm watering the garden and water gets on the bloom, the bloom shrivels up and doesn't perk back up later.  It's a desert plant and it's perennial.  Great... a monster that stays all year long!  They are hardy (no kidding!), low care (of course) and drought resistant and cheap to buy (especially when given from friends).

So, does it stay or does it go?

So far, it stays.  It's definitely the fastest grower in the garden as of yet.  But it hasn't collided with any other plant... not yet...