Trap
She should have known it was too good to be true. There was no way the turians could have disabled the Collector ship just by themselves. But she went along with the Illusive Man's plan and boarded the ship.
And he led them straight into a trap.
Luckily, everybody escaped unharmed. But that didn't make Shepard feel any better. She spoke her mind to the Illusive Man afterwards about what he'd done and all he said was the same thing.
"We can't sit around and wait".
Through all her anger, she hated to admit he was right. But Shepard didn't risk people. There were always alternatives.
At least they acquired more information about the Omega 4 relay. The suicide mission was fast approaching. Then she could be finally done with Cerberus.