2000 SLT Alternator?????

Hi,
2000 Dodge Durango slt 4.7 4wd. Temp last few days out side is 0 or a lil above. Very cold here haha. Start truck no problems. Drive to destination. On trip home(7 miles) Its snowing i notice wipers are very slow. turn them to high still real sluggish. Stereo turning on and off. Windows wont go down. And this whole time im still cruzin at 40ish. Check gauges light comes on. I notice all the gauges are @ zero Battery, Fuel Oil, Temp. Go home turn it off. 10 minutes later starts right up. bat gauge reads 14ish, then drops to zero. Buy new battery. hook it up. WOW! Never been soo bright. Everything works. Bat gauge 14+. This lasted less than a minute. Turn off. Wait. 5 mins later Starts right back up with out hesitation. bat gauge at 12 maybe 13. turn on lights right to zero. Repeat same. lasts a few minuts gauges go to zero all power accesories very slow almost non working. Truck runs tho. eventually dies, sputters but well after gauges conk out. Does any one know what could be wrong. Is it the alternator? Need to be sure of problem. Very broke.loll oh and i did notice last weekish the bat gauge being very high like almost 18. probably 16ish. i thought that was a good thing.

well i gotta give a BIG THANK YOU to every 1 on this wonderful forum who helped me with my problem. You all were so much help. But really why do people even post here? Seriously, why? I figured it out myself. So if any1 has the same issue . it was the Alternator Fuse. Thats it. A $3 part. Im sure no one will ever view this. so what eva.

i read it!