Transmission Solenoid problems of the 2006 Nissan Xterra

I have a 2006 Nissan se Xterra 4. 0 4x2 automatic -I started noticing when gets speed up to 45 miles it is making a hard shifting and when slowing down making a hard down shifting as well. I mostly notice this when the vehicle is already warmed up and stop and go traffic is when it starts acting up, like a clunk noise and feel like it is loosing power in the transmission. It was a cold day and when leaving work and I backed up and then put in drive and started to move forward all of a sudden the service engine light came on and it felt like I had lost power to the transmission. (bogged down feeling) I had to press further down on the peddle to get the Xterra to drive. I drove home slowly with my flashers on praying to god I would not break down within the 7miles. The next day I drove 2 miles to oriellys to pull the code p1754 with several others. I drove to a transmission shop and was given a "worse case scenario" charge of about $3300. 00 -I still owe $6000. 00 for it! I started to investigate the issue online with all of the forums/parts/rebuilds and such and found that the transmission is the issue with the coolant line in radiator cracking and leaking atf into transmission causing problems with corrosion in the valve body and transmission (o rings/seals) causing to be replaced which is (faulty engineered/manufactured highly expensive defect) at around 100,000 miles and cost is $1100. 00 for body valve, rebuilding transmission ($2800. 00-($5000. 00 for new) and replacing the radiator $ 260. 00 and lets not forget about the labor at about $110. 00 an hour for around 13 hours. Who has this kind of money for this repair?? I love my Xterra but not at this cost since I found out that every 100,000 I will have to replace the $1100. 00 transmission valve body (solenoids failing)!! I am very disappointed with Nissan.