How did Wesker betray Alice?

How did Wesker betray Alice? Wesker meets Alice again in person after she is brought to the Oval Office. He injects her with a watered-down version of the T-Virus, falsely claiming that she now had all her powers back. Wesker explains that she is THE weapon that humanity needs to win the war against the Red Queen.

Wesker meets Alice again in person after she is brought to the Oval Office. He injects her with a watered-down version of the T-Virus, falsely claiming that she now had all her powers back. Wesker explains that she is THE weapon that humanity needs to win the war against the Red Queen.