I wouldn't stop being aggressive! I have no idea...this is just a guess....but maybe (just maybe) your friend who works there isn't the best source/reference? I don't know your friend, but when I worked as a tech on a busy unit the nurse manager was always telling us to send people her way! If she didn't call you after all that...maybe you shouldn't use her next time. No offense. I could be completely wrong.
I graduate in December and tons of my classmates already have jobs. Last week I started feeling a little behind the crowd so I started applying to all kinds of positions online, and for the ones I REALLY wanted, I followed up with an email directly to the recruiter or manager that said, "I recently applied for X position. I just want to follow up with a resume which I've attached and introduce myself." I got a few emails back that said, "Thanks for your interest. We are looking for someone immediately and you don't graduate until December, but please contact me again when it's closer to time." I figured that's better than nothing. They really didn't have to respond! So, I will contact them when it's closer to time...
Then, I got an email back saying, "we will contact you soon," and they called me the next day. I had an interview, and tentatively have a job lined up for a January start date. It's at a state hospital that's a little farther from home than I'm crazy about, but I'm going to keep looking and keep that as my back up. It actually is in the field I really want to work in. I also applied for a couple jobs with a fairly large hospital system in the area today. Afterward, I sent the recruiter for that system an email saying, "Hi. My name is blah blah...I applied for some jobs today and was just wondering if there are any career fairs coming up in the area soon?" Really...I'm hoping she'll take the time to pull up my application and forward it on, but it was a good "in." I'm sure she'll at least email me back.
I was hesitant at first about emailing people directly and didn't know if it was a professional thing to do, but I figured....they are never going to see me or hear from me again anyway if they don't like it. If they do like it then it could land me a job. Actually, it did..the very next day. Keep on being aggressive...it'll happen for you!