Hey DevD,
It sounds like you've already received some good feedback. I agree with most, mixing isn't step-by-step, like using a cookbook. It's learning, trying, messing up, getting frustrated, trying agin, and then continuing to learn. It's tough, and not everyone can do it well. Wondering why your mixes don't sound like "professional" mixes would be like a little league player saying, "well why don't I perform as well as a Major league player?" It's about experience, time, passion and commitment.
The fact that you're posting on this forum means that your committed, so now you need to get some experience. Though, to be honest, it's a long road, and it can be super frustrating if you let it. Unfortunately it's hard to ask someone to write you out a solution to such a complicated, and subjective process. What you can do, however, is spend time finding techniques, and implementing them one by one. Try stuff out... a lot. Try stuff over and over again until you can not only perform it, but you understand what is happening conceptually. For example, you'll find a lot of YouTube videos that say something like, "get your kick and bass to break through the mix". Go and watch a few of those. You'll learn that when two things share very similar frequencies, sometimes you have to make room for both through EQ, multi-band compression, panning, leveling, depth, etc.
The reason we all hear the dreaded "muddy" descriptor over and over again, is because almost everything that makes a sound shares these muddy mid-frequencies. Now, not all of them are sharing the exact same frequencies, or we'd just tell you to cut "X" frequency, and it won't be muddy anymore. As you can see, explaining what's going on is difficult.
As for a reference track, I am much more surgical. I listen to how the kick sound, and compare it to mine. How do the guitars sound? What's their top-end like? Oh shit, did I just spend 8 hours mixing, and cut out too much high-end info? Where does the vocal sit? I also pull out an EQ on the master buss and play with high- and low-cuts; both on my track and the reference. I listen to the two and compare how they both sound when everything above 150hz is cut out. Does their track sound tight and clear? Does mine sound unfocused and blurry? Reference tracks are hugely valuable, are shouldn't be limited to comparing loudness and stereo spread. They bring you back to a controlled sound source, after soloing, EQing, tweaking, etc., your track for hours at a time.
My best advice to you is to find a working mentor. Someone who can let you watch them mix and share what they're doing while they do it.. and WHY their doing it. And then, practice over and over again... and again... and again. Keep in mind, the pros mix 8-10 hours a day between 4-6 days a week. Put in the time, enjoy the process, and keep your passion, and hopefully one day you'll help someone else learn to mix.
All the best!