Been turned down before, and went 3 years before getting hired after I left the military, so I know what a blow something like this is, especially to your ego. It's deflating to wonder why you weren't hired when you seem to have everything your prospective employer is asking for.

Don't doubt yourself. Not being hired is NOT a reflection of your abilities.

You could have been turned down for wearing the wrong color tie. Or you reminded the interviewer of someone they hated. Or they didn't like your accent. Whatever...this industry is so fickle...

Just keep working toward what you love doing. Accrue meaningful flight time, keep networking too. Meeting the right person is better than all the flight time you could ever have. I can't stress this enough.

The interview coach is a great idea. I had some bad habits regarding nervous fidgeting and posture that were corrected by an interview coach.

Also, make sure before you interview that you get the "gouge". That means knowing all the questions they are going to ask, what aircraft they use for the sim eval, what the sim profile is, facts and figures about the company etc...EVERYTHING. Then go rent time in an equivalent sim with an instructor and fly that profile a few times. You don't want any surprises during the interview.

That's all I can think of, for the moment. Hang in there.