The Mercedes driver suffered another blow at the Mexico City Grand Prix last weekend, finishing sixth after starting on the front row before his car suddenly slowed.
Italian 20-year-old teammate Kimi Antonelli finished third in the same race to become Formula One's youngest champion.
"When you get kicked to the ground, you pick yourself back up. And you get kicked down again, you pick yourself back up. And I was hoping to do that maybe twice in the season, not every other weekend really," Russell told reporters on Thursday ahead of a Sao Paulo Grand Prix that could secure the 2026 constructors' title for Mercedes.
"When you're away from home three weeks in a row and you have another race like what happened in Mexico where a chance of victory, a chance of the podium just disappears totally outside of your control, it's tough to deal with", he added.
The Briton, who entered the season as the title favourite, pointed out technical issues had affected him at 14 races but added that it would be naive to blame bad luck alone for his failure to mount a sustained title challenge.
"I don't think the team have let me down honestly because these things do happen. Nobody intends for it to happen. We're all trying our best to deliver the best," he said.
"And last year, we had a car that was extremely reliable and we only finished fourth of the championship. This year, we have a car that's extremely fast but has been unreliable. So which one do you prefer?"
Russell, 28, took the first win of his F1 career at Interlagos with Mercedes in 2022.