Help with seating on the bike!

When I started training for my first triathlon, from a non-cycling background all my rides were outdoors and the saddle was comfortable enough for me.  Then when I got a bike trainer and started to do indoor rides the same saddle for the same duration rides became very uncomfortable late in the ride.  My coach said that I probably changed positions more often outdoors to take corners, got around obstacles in the road, to climb hills, etc.  but that as I spent more time on the indoor trainer that I would be able to go longer and longer without discomfort.  That was true.  Over time I got to where I could go longer and longer in the saddle.  I got a new bike later on and the bike fit and the style of the saddle made things uncomfortable again.  I got the fit the best I could but still struggled so I changed saddles to a style like my previous bike and the improvement was instant.  After struggle for week on a saddle that was not the right shape for me, for the first pedal stroke with the new saddle things were much more comfortable. 

So, 1) try to change your position more on the bike by standing up in the saddle periodically, etc.

      2) try to go longer and longer in the saddle with each ride.  With training, you will be able to go longer without discomfort. 

     3) make sure the seat height and position are fit to you

     4) make sure you have the correct shape saddle.  You can read about the shapes in the recent thread on "the latest thing in tri saddles"?  

Not a female, but some likely causes to your complaint:

Improper bike fit
If your seat is too low, your legs don't extend properly and more of your weight is transferred through the saddle rather than through your feet.  Numbness/tingling result from the extra pressure.
If your bike is too big, you'll be "stretched out" between the saddle and handlebars which similarly applies extra force on the saddle in addition to the stretch rotating your nether regions forward.  Double-ouch.  

(Time In The Saddle) helps.  Early in the season, 30-45 minutes can be hard to take, but building up SLOWLY can get you into hours.  

You can search for the holy grail of saddles.  Another common solution is to angle the saddle ever so slightly right or left (possibly also down).  Very small adjustments like this can have dramatic changes to how the weight is transferred and pain/numbness/tingling associated with the pressure.  Ideally, any saddle pressure is transferred through your "sit bones" and not other highly sensitive soft tissues.  

Chamois cream (aka butt butter) applied to your skin can reduce friction between your nether parts and the pad in the shorts.  This can help reduce numbness/tingling/soreness.  

If you haven't, invest in a bike fit before buying a lot of other things.  

^^^ This.  Often "saddle soreness" has nothing to do with the saddle itself.

The two bike fittings I've done over the past ten years have been the best money I've spent in this sport.