DodgeForum.com - 1998 transmission problem

I know there is probably a thread out there that has this on it but I don't have the patience to go through all of them to find it.
I have a 1998 Dakota slt 4x4 with the 5.2L magnum automatic transmission in it 190 000 km on it
about 5 days ago my truck ran and shifted perfect than 4 days ago i started getting a rough shift into 1st and 3rd than it was pretty much gone the next day. So it sat for a day than yesterday when I went to go drive it something didn't feel right, about 10 mins into driving it I know something was wrong, I could let my foot off the brake when stop completely and my truck would not move just like if it were a standard and when i would give it a little gas it would barely move as i kept pushing it would move more and more than when I started driving it would shift funny, like 2-3-4-3-4 all at once and I was only going 60km/h(btw im from Canada). When I got home I went to back up beside my garage and i didn't move very far, I had to almost floor it to get into my spot slowly. So this morning about 20mins ago I put it in neutral and let it run for a good 15mins and still nothing, and with my truck on a slight slope it would roll forward until I stepped on the gas a bit to get it back in my spot. I reminded me of a standard transmission. I talk to my local transmission repair shop and they said it would cost 1500-2500$ to fix it. I don't have that kind of money right now since I am paying for my wedding in a few months so if anyone can attempt to diagnose the problem asap that would be great I am handy when it come to vehicles just kinda new to transmission.
Thank you