As a CS major (junior), I often find that when I think assignments/exams are uncomfortably hard I tend to pour my energy into other hobbies that are seemingly less stressful at the time and convince myself that this new fleeting hobby is my new passion (like the time I decided to write the first ten chapters of my great new novel in the middle of a 24hr coding exam). Moral of the story: Coding is hard, and just because it comes easily to someone at first doesn't mean that there aren't going to be those days when it's frustratingly, nail bitingly difficult. The reason I say this is because you sound as if you're inclined to give up or cease to try when things get difficult. If coding really is your passion, the best advice I can give you is to find a project you love and obsess over making it perfect every single day, even when you run into a problem that is seemingly impossible to solve.

As for technical advice, I would suggest you familiarize yourself with as many languages as you can. I started coding in C, and while I rarely use it for anything other than assignments it has definitely helped me in terms of understanding concepts and constructs for other languages. I've never used RoR, but I'm assuming that you've at least learned the basics of deploying a web app. Try learning Python/Django, JSP (I hate it, but lots of small businesses in my area use it and it's great to throw on the resume), PHP, etc. You'll find that there are a lot of similar concepts.

I'm in the job hunt myself and every single recruiter I've met has said that the best thing you can do is to expand your programming skill set. If you've even so much as finished a basic tutorial in a language, list it on the resume. Build up your portfolio with as many completed projects as you can. Don't listen to what you're "supposed" to do - I was "supposed" to be an English major because I got an 800 on the SAT verbal. The point of CS is that you take the rules and bend them beyond the point of recognition, and the sooner you start thinking this way the better.

Anyway, good luck and I can only hope that the passion you have for coding now stays with you during those tough moments ^.^ (Oh, and don't worry too much about familiarizing yourself with TDD, Agile, etc. There are a ton of books on safari on the subject - read those, familiarize yourself with tools like git, trac, or any version control system, and you can get by)