The End of Stealth?

This is all theoretical, but it involves some future concerns I’ve been thinking about for a while. I wanted to air it out here to see what people with some knowledge on these matters think of it all.

How far into the future can stealth technology go, and what happens if radar technology ever gets to a point where fighter-borne and other forms of radar can reliably detect stealth aircraft?

Radar technology is consistently improving, and with other nations ready to deploy stealth aircraft of their own alongside America’s B-2 and F-22, it seems only a matter of time before someone (likely the US looking to guard its advantage against PAK-FAs and J-20s) begins pushing breakthroughs in technology that will allow us to mount more powerful detection systems on fighters capable of spotting other low RCS jets.

If such technology spreads with any significant extent to other nations, what are the implications for air forces that have spent fortunes and built futures on the benefits of stealth aircraft? Is there a way to protect that investment and make stealth aircraft less visible? What would happen if such radar-advances spread at a pace faster than such airframe improvements can be made?
Furthermore, is it possible that such technology might exist, though obviously not in a publicly acknowledged capacity?

Also, as a corollary to this, what is the potential for advances in Electronic-Warfare weaponry and how do you see it impacting the future of air combat? Can anyone envision a scenario in which an abundance of powerful EW systems leads us to rely on older, less technologically advanced systems and technology in combat?