There are at this point many things it could be:

It might be flooded now. Try holding the accelerator pedal 1/2 way down
and starting it. It may take a while before it starts, though. It may
caugh to life with a puff of smoke and smell before it runs normally
again.
If you are getting gas in the cylinder head (where the plug is
located), most likely your problem is not your main relay. Your fuel
pressure might be bad, though, but one would think it would do
something..

So when you say that the plugs were checked for fire, were they checked
on your car? I.e. they were checked by taking them out, one by one, and
holding them close to the body while trying to start the car? Or did
you bring them someplace to be checked?

If the sparks are coming and you are getting gas and if you still can't
get it started, it could be timing related. It does happen that the
timing belt, when getting older, skips a couple of teeth and the timing
is now off where the car will not start or run at all. That will
require the timing belt to be replaced. How many miles on your car and
has the timing belt ever been replaced? (it is an expensive repair -
you'll remember if you had it done).

It is a little suspicious that your battery died to the point where you
could not get a peep out of the starter. When you do get it running,
make sure you are getting about 14.5 volts on your battery. Your
charging system (belt, alternator, etc) could have a problem (too).

How comfortable are you around working on cars? Just checking, because
I wouldn't want to steer you in a direction you don't really feel
comfortable with.
If cars are not your thing and we're getting into where it takes
special tools, techniques and fixtures, you may want to bring it to a
mechanic.

Remco