What should I do next?

I've got a 2013 Ford fusion. Love the car, just not sure it's worth fixing up. I hardly have enough money to fix it, but if I save up I could. I've got an incredibly slow rear main seal leak, a pretty significant coolant leak coming from a 3 piece connector near the reservoir, and i need new lower control arms and struts. Worst part is, the car is from Massachusetts, where I used to live and where it spent most of it's life. The previous owners never protected it from rust, and almost every bolt on the bottom of the vehicle is rusted beyond recognition, breaking them off being the only way to fix it. As you can imagine, the frame is pretty rusty, too. Its not unbelievably bad or dangerous, mostly just rusted edges. Being in texas now, the rust isn't getting much worse. There is one very small hole rusted out in the rear, but I'm certain it could be welded with some extra metal.

The question is, should I just drive it into the ground and junk it when I'm through with it, or should I fix it up to keep it going a while longer? The engine is still in good shape, not sure about the transmission, though.

2013 2.5L SE with 163000 miles on it.