When you've given up your old ideas about something, or retracted a statement you made earlier, you can call it abjuration.
Your conservative uncle might be frustrated at the abjuration of your former political opinions, especially if you become a progressive Democrat. Many people experience an abjuration of their religious beliefs, renouncing one faith for another or dropping religion from their lives altogether. When you abjure something, you give it up or renounce it. The Latin root is abiurare, "deny on oath."