OP, I *so* feel you. It's a major coincidence, it just so happens that I am about to drop linear algebra very late in my term because I don't understand the first fucking thing in this class. I am all A's and B's in my other courses (CS degree), I finished high-school vectorial algebra with an A-, but once I got into this prof's class, it's as if he's speaking another language. I got a block a few weeks into the semester (first term in uni), and it all went downhill from there.
What little I can share, is I tried Gilbert Strang's manual, "Introduction to Linear Algebra" and it was the closest thing I had to understanding something. It's actually a companion book to his linear algebra course at MIT, that you can follow for free on
ocw.mit.edu . The Khan Academy videos aren't bad either, but they're not a cure-all. Like I can't figure out how to adapt the Gram-Schmidt process to 3-component vectors... I'm in a bad place right now.
Also, if it helps you in terms of moral support, both my parents are engineers and they both loathed linear algebra in college. It's not an isolated phenomenon. (Even in my current class, about 25% of students share my problem). Unless you have a gift for maths in general, or a brilliant prof, you're screwed.