If your opponent is seriously just building mass tanks as Germany and sending them East there’s a handful of tools available to you to put up a fight:
1. As USSR, forget about trying to hold Leningrad and concentrate your forces in West Russia. Your objective should be to trade Ukraine lightly (as in, send 2-3 of your Infantry + air support to kill 1-2 German Infantry) each turn while waiting for either Germany to make a move or for help to arrive from the UK/US.
2. If Germany just pushes their entire army into Ukraine blindly, you can pull off a “strafe attack”. Basically, you send in several ground troops you have available + air support, stay for 1-2 rounds, then retreat to either West Russia or Caucasus (where your surviving forces will be reinforced during NCM by fresh troops from Moscow + newly built troops. The idea with a strafe is that you’re trying to do one of two things:
A: Remove all or a large portion of the German Infantry from their stack. This will make Germany’s follow-up attack on your forces more cost ineffective to them, as they won’t be able to assign losses to expendable Infantry anymore.
B: If Germany is seriously just building mass tanks, then you’ll be trading Infantry for Tanks in your strafe attack. Even if you take sizable losses there’s no way Germany can take 2:1 IPC value losses for an extended period of time. It’s suicide.
I can go into more detail on strafing tactics if you want, but I’ll leave it at that for now.
3. Fly Fighters from UK -> West Russia (or Moscow if the game gets desperate enough, but you’ll need to by a CV to do that).
4. Have the USA focus on the Pacific. UK stands absolutely no chance against Japan alone and you need to clear out the money islands ASAP to stop Japan from becoming a monster and winning by itself.
5. Don’t just spam amphibious landings in Europe. Small landings are too easy for Germany to repel. Instead, focus on building a large fleet as the UK and threatening to land troops in Europe. This will force Germany to divert an increasing number troops from the Eastern Front to guard Europe. If Germany ever leaves a territory empty, just land one Infantry there to collect the fre IPCs and force Germany to waste effort retaking it on their turn.
6. Your main landing target should be Norway/Scandinavia, in case you weren’t aware. Germany can’t defend that part of the board reliably so it’s a good boost to the British economy (which they’ll need since more often than not Egypt+Africa will fall to the Germans for a large chunk of the early/mid game). Plus, a healthy force of British troops in Scandinavia forces Germany to commit forces to defend the factory in Leningrad, lest they allow the Soviets to reclaim it.
7. Never commit a large invasion force to France unless you’re certain it can survive the German counterattack. If you’re going for a last minute desperation play to save the game, land in Karelia (Leningrad) instead. It’s worth less IPC, but is:
A: Farther away from Germany’s centers of production
B: A Factory for the Soviets, who can stick two extra units there on their turn to help hold the territory.
C: An immediate threat for the Germans in Russia, who will need to waste a turn or more attempting to dislodge the landing party before they can finish off Moscow.
Your friends (and the other posters in this thread) aren’t wrong, though. 1942SE is a terribly balanced game to the point that Allies basically can never win in a no-bid game when both players are experienced, but I don’t think your opponent is playing particularly well as the Germans, so I believe that you can turn the tables on them.
You also may want to look into the Larry Harris Tournament Setup, as taamvan suggested. It’s a lot more balanced than the regular setup and it might be easier to sell your friends on the idea of a “cool new scenario on the same map” than it to sell them on a bid system.