Alicent is a traitor.

The thing Alicent (at least in season two because season one Alicent seemed cognizant of that fact), the showrunners and their defenders ignore and what makes her deal with Rhaenyra be nothing but pure is that the Dance of Dragons is a war of annihilation.

Rhaenyra is absolutely not going to forgive Aemond for murdering Luke and Rhaenys. Everyone in Rhaenyra's faction would turn against her if she did so.

Aemond has an army and rides Vhagar, the largest dragon in the world. Even if he is outnumbered, Aemond has no reason to kneel to Rhaenyra since he knows for a fact it is either winning or dying for him.

Rhaenyra cannot bring the peace she desires without getting rid of Aemond and his army. Cole and Gwayne, both who have been nothing but loyal to Alicent, are in that army.

The deal Alicent cut with Rhaenyra in S2E8 does not buy safety for her family. It doesn't guarantee that Aemond, Criston, and Gwayne will surrender, or that any attempt they make to surrender will be honored by the Blacks. It doesn't guarantee that Daeron and the Hightowers will stand aside and watch as Rhaenyra murders their King and crown prince.

Alicent didn't just sell Aegon to Rhaenyra. She sold her sons, her lover, her brother, her father, and her entire extended family.