First off, congrats for being motivated enough to look into the internship idea. They can be a great deal or a total waste of time. Most of that generally depends on what you're hoping to get from the experience. If you're looking for a fast track to a job somewhere, then your summer would probably be better spent getting the rest of your ratings an possibly instructing a little bit.
If you're more looking for industry experience, then you're on the right track.
Are you sure you want a career with the airlines? This may be a good way to see if it's for you or not. Maybe you'd be better off interning with a company outside the industry to see what else is out there. Especially in this industry it's important to have a backup.
Good luck and pm me if you want some insight on my experience. I interned with ASA in college and it turned out to be a great thing even though I didn't end up flying for them. Stay positive and realize that while this may never be the career it once was, you'll still like your job a hell of a lot more
than your friends working in the cubicle.