Learning judo is frustrating! I remember encountering that frustration learning judo and I just tried to endure it and work harder. Probably not the best way - I could have been trying to work smarter instead of harder if someone had been there to encourage me. .
I remember after about 2 years of almost-daily practice I was leaving class one day and my instructor stopped me and said, "So, Pat, are things starting to fall into place for you in judo? Starting to make sense and get better?" Well, he just caught me at a bad moment and I started crying and told him, "No. I get more angry and more hurt every... single... time... that I come to practice. Every single fall I take gets worse." .
He asked me why I put up with that sort of punishment without quitting and I said, "I don't know. Judo is just something that I can't quit. It's stuck down deep inside me." You'd think that a moment like that would have been the turning point, after which it would have started getting better, but no. Judo continued to hurt and frustrate me for 2-3 more years until I finally graduated and left that university. .
When I started teaching in McComb in 1996, I stumbled into a group of fanatical students who absorbed whatever I would teach and would clamor for more. They wanted to learn judo so I started teaching judo and I promptly affiliated myself with the highest-ranked judo folks I could get my hands on even though it meant having my instructors in Texas instead of here in Mississippi. Mac McNease came to do a seminar at my fledgling club in McComb and that was the turning point for me. The point where I stopped doing judo despite hating it and started doing judo because it was amazing and I kinda liked it. What was the little piece of encouragement that he gave me? He told me, "Pat, this is judo. It's supposed to be easy. If it is not easy then you are not doing it right. Or you are trying to do it wrong." .
That's when I really bought into Kano's maximal-efficiency-minimal-effort ideal and when I started improving and enjoying it. The moral of that story is, if you are frustrated with judo, I know where you're coming from.
One of the most frustrating things is being crushed into the ground and smothered in randori and being unable to apply the positional escapes that you are learning. As for general advice that I'd give a frustrated student on the ground...
A lot of people have tension headaches after class from being wrung out on the ground or from being whipped into the ground. This gets better within 5-6 such classes. You'll notice a survivability turning-point within about a half-dozen strenuous randori sessions. I can just about guarantee that.
There is a difference between learning the mechanics of an escape during drill time and being able to find that escape during randori. In randori, when someone is crushing you, you have to first find a way to get some respite for a moment. This can mean framing under them or shrimping slightly out from under them or just getting them off your diaphragm and floating ribs.
During that respite you need to start working your three general groundwork principles that I gave you. That is, get two hands on a point, start with your shrimp-bridge type motion, and insert your knees and elbows as spacers whenever you can.
Once you get those three principles going, the situation will tend to rapidly turn into something very similar to one of your escape techniques.
You need to do many, many reps of the escapes that I show you. The most important of which are probably uphill escape from kesagatame and bridge&roll from munegatame.
You need to to start each class with a few rounds of the mobility cycle. Let a partner get into a hold with weight on you and keep it there as he moves from hold to hold so that you learn to survive on the bottom while being pressed. And not just to survive but to be able to rest and think while on bottom.
You also need to start each class with a 2-hands on a point drill for a while. You can practice this at home by tying a belt or a gi around a dummy, getting under him, getting 2 hands on a point, and shrimping out from under him. Push the dummy across the mat one direction while you shrimp your butt the other direction. You might have to reposition the dummy a little but when you reverse and shrimp with the other leg, it should throw the dummy on your other side. So you shrimp while tossing the dummy from side to side.
Keep a good attitude. We generally learn to solve the hardest problems we can first, then everything else gets easier and easier. As my instructor says, it's easy to prevail when you're stronger and better and on top, but the guy who can prevail even though he is laying in the ditch bleeding is truly remarkable. You're learning to get out of the ditch!