Reddit reviews Discrete Mathematics, Student Solutions Manual: Mathematical Reasoning and Proof with Puzzles, Patterns, and Games

First of all, I am glad to hear that your attitude towards math has changed so drastically! Welcome to the dark side. As for where to start relearning math, that probably depends on where you're starting from. Have you taken any classes on discrete math or linear algebra for your IT major? How about calculus?

If you want to work in mathematics, then you probably want a light introduction to proofs. Most undergraduates in math and computer science at my university use
Discrete Mathematics: Mathematical Reasoning and Proof with Puzzles, Patterns, and Games. I personally recommend How to Prove It by Velleman, which promotes a structured approach to proving that jives well with the step-wise refinement approach used by people in comp prog and comp sci.

If you have had some calculus, another good place to start is Calculus by Spivak. It will start you over from the basics, but with the rigor one should expect from a mathematics course.

Of course, I'm just making guesses about your background and your interests. What do you think you'd want to do with math or physics, or both? Perhaps you might enjoy scientific computing? If physics (or maybe even engineering) is your thing, then skip the first two books I recommended and try out Spivak. From there go on to books on linear algebra and differential equations -- the necessary math background -- while also checking out some physics books (I have a few to recommend, but that's off-topic. Let me know if that's something in which you're interested).