There are a lot of things that could be at fault here, and it’s hard to say what it is in your case.
First of all, there is certainly some truth to the fact that females get preferential treatment in hiring. But there really aren’t all that many women you have to compete with, so you should be able to get by anyways. Besides, it also sounds like you are hoping that you will get preferential treatment because you have family in certain companies - this strikes me as a bit of a double standard.
If you’ve gotten that many interviews, your resume is probably good. Not necessarily perfect, but it gets you the interview. As for why you don’t get the job, it could be a number of reasons. Maybe you haven’t applied to enough jobs (you need to apply to more than you think because job searches are tough), maybe you need skills you don’t have (learn them to make yourself more marketable), maybe you just got unlucky enough to be outdone by some other candidate who was a better fit 11 times in a row (it happens), and maybe you are doing something wrong. Don’t expect HR to be honest with you either because first and foremost they have to shield themselves from lawsuits from unhappy applicants.
If you still can’t find an internship at the end of it all, I recommend you do the following: look at the specific skillsets that companies commonly want (CAD, programming, etc are big ones for MechE, for example) and learn them. Also learn to tell the employer exactly what they’re looking to hear in regards to your work experience, even if it is only partially true. Also helpful is to find a mechanical job, even if it isn’t engineering, because a lot of companies like that sort of thing. Is it better than an internship at a well-known company? No. But it is far, far better than doing nothing.
As for the GPA, I recommend putting 3.8 as your GPA if yours is higher than that. Trial and error taught me that that was the ideal GPA for appealing to most employers.
Echoing: don’t come in with a chip OR that we are “lucky to have you.” Better to say you work hard but know you have a lot to learn and are eager to do so.
Things not mentioned: Make sure your physical appearance is up to snuff. Appropriately dressed, hair cut, deodorant.
Use good manners.
And I hate a crummy handshake. As a woman lots of men do some weird floppy handshakes. I don’t know if they do the same to other guys but yuck.
Female do not have preferential treatment. There are plenty of females in CS that don’t have internships.
This statement is not true for engineering as a whole. It may be true in CS (I have no experience in that field), but in many other STEM fields, employers are very happy to hire female candidates both for their diversity statistics and, probably more importantly, studies have shown that staffs with a more even proportion of men and women work better.
You work directly or indirectly for government. But not in commercial. I can attest to you she was rejected out of a few companies because she didn’t passed the technical questions. Same with her friends, they both are good students with high GPA.
Well that’s no surprise. Diversity statistics or not, you DO have to prove yourself capable of doing a job to be accepted. Not all jobs are technically difficult though.
Particularly in engineering, through my work I have seen some females unable to meet deadline and the work was taken away and give to another capable engineer. In high tech, they don’t care about statistics because it does crap for the companies and its deadline.
From what I’ve seen, less of an issue in CS, where supply and demand (or available workers) isn’t really too bad for CS grads. Not so much in the more traditional engineering fields, where jobs are notably more scarce.
I don’t think poster has been back for a couple weeks.
I thought it was a fake post originally.
Well I’m mostly posting for the benefit of anyone else reading. Strange that people would bother with fake posts - I really don’t see a good reason to do that.
The word is banned on CC but it seems to rhyme with roll.
Thanks for the advice guys! I actually just received a job offer today!!! 
The 12th time’s the charm.
Awesome!!! I think I’m going to bookmark this thread so that I can read through it - there’s some great advice on here.
And that right there is job searching in a nutshell.
chickenLover - So happy for your success! I assume you will be accepting the offer?
Do you care to share your experience?