Honestly I'm a little surprised Russian counter sanctions haven't been harsher around the exports of things like oil, gas, rare metals and minerals. Doing so would hurt them too, just like our sanctions are going to hit the US and especially Europe pretty hard, but they'd cause considerably more pain to the US and Europe. Perhaps they're planning on using them as economic bargaining chips if people ever come to the table properly, or maybe they think maintaing some trade buys them time over further escalation.

From what I'm reading, Russia could go on indefinitely even with the current sanctions regime. The economy will take a huge hit, and may stagnate in the future, but they've done enough reindustrialisation and built enough alternative infrastructure for things like payment systems, along with places like China and India, that they pivot there instead.

There's also the fact that as oil prices keep rising because of this, that'll start a big new influx of cash for them as a net exporter. That's why the US state department is going round trying to somewhat normalise relationships with countries like Venezuela to produce more oil (although they've backtracked on that after the Senate through a fit, publicly at least). Increased supply and production would help to neutralise that benefit for Russia

So on the one hand the US/NATO are hoping to inflict maximum economic pain as fast as possible to put pressure on Putin. While Putin is hoping he can weather the storm for long enough to complete the pivot to Asia. Either way, Russia will continue in one form or another.