How much money have you invested? How profitable are you?
If you haven't invested a lot, and you are very profitable, then you should compete with them. You have low risk and high reward.
If you've invested a lot, and you aren't very profitable, then I would probably reach out to them to see what arrangement you can set up. The idea here is that you want to protect your original investment. If they start soaking up customers and you guys start losing money, then you go out of business and lose all your money.
And if you're kind of in the middle, it's a bit of a coin toss. You probably should double down, acquire some big customers and more traction, and then decide if you should sell the company if future prospects don't look good.
A profitable buyout is a profitable buyout. If you don't see a path to becoming a massively profitable business, then go get bought (Github) or set up a scammy IPO (Blue Apron)