I do not really care who made a game. It just happens that games that catch my attention often are made by Nintendo - so, yes, I will probably follow wherever they go.

With the NX launching alongside a game like LOZ Breath of the Wild, if it fails Nintendo have only themselves to blame.  Mario Kart 8, Mario 3D World and Splatoon were the only real console movers the Wii U ever had.  Nintendo had better have a stellar lineup of titles ready for the NX launch or shortly thereafter, along with versions of all the big 3rd party multiplatform titles, otherwise the NX will lose all the hype and momentum built up from Zelda shortly after launch.

Not if their system after NX is successful. Nintendo had two major failures in a row with N64 and GameCube, and then they had a winner with the Wii.

I had more fun with my N64 than GCN or Wii, so whatever, market success doesn't impact my enjoyment of a machine, especially when it doesn't really translate to anything tangiable for the consumer. 

I will be with Nintendo until the bitter end.

A better question would be, will you support Nintendo if they went Third party?

I don't understand what you mean by fail, but why abandon them? It's not a marriage. I didn't buy a Wii U. I won't buy a PS4 or a Xbox One. It's a matter of games, if they release something I really want to play, I'll buy their console. All the important stuff is already on PC, it's not like I care if Assassin's Creed is on Wii U or not. Currently I want to play the new Zelda game, so if I'm still interested in the game by the time it is release, I might get a Wii U or NX, depending on the price.

I don't think that is true. Had Wii U sold well, I bet we would have seen mainline installments to Kirby, Fire Emblem, Animal Crossing, etc., games like Ultra Smash and Starfox Zero would have been of higher quality, Pikmin 4 and Zelda BotW woulda been Wii U exclusive, and we woulda seen price cuts and remodels.

That's completley irrelevant, you are still playing the game, just because people with a NX can play it too does not translate in anything bad for the consumer.

i will still support them because competition is good