When painful thoughts and feelings due to abuse or memory of abuse arise, it could be difficult to stop such thoughts and feelings. We should immediately turn our attention to the Dhamma, and recite or read the Buddha's teaching as summarized in the first post of this thread (so it's very helpful to be able to memorize them, which are the best medicine).
Ask: "What is the source of sorrow, lamentation, pain, grief and despair? How do they arise?'' (SN 22.43)
Recognize: I'm having painful feelings/thoughts (and perceptions/volitions), but they are only feelings/thoughts (and perceptions/volitions); they are anicca, dukkha, and anatta -- they are not you, not yours; let them go.
After such hurtful feelings/thoughts stop, then recite/read the metta sutta (Sn 1.8), and radiate metta to ourselves, to the abusers, and to all.
Realize that we could turn the abuses we suffer to great progress in our Dhamma practice, by cultivating all the 10 paramis (and even beyond):
Dāna pāramī : generosity/forgiveness
Sīla pāramī : proper conduct
Nekkhamma pāramī: non-ill will/non-hatred/non-hostility, non-cruelty/non-harming
Paññā pāramī : insight of the five aggregates' anicca, dukkha, anatta
Viriya (also spelled vīriya) pāramī : diligent effort to avoid/stop the unwholesome, and arouse/develop the wholesome
Khanti pāramī : patience, tolerance, forbearance, acceptance, endurance (& humility, contentment)
Sacca pāramī : truthfulness, honesty (by acknowledging our own mistakes and wrong doings)
Adhiṭṭhāna (adhitthana) pāramī : determination (to stop the unwholesome and to develop the wholesome)
Mettā pāramī : loving-kindness
Upekkhā (also spelled upekhā) pāramī : equanimity, serenity
"Though touched by worldly circumstances,
Never his mind is wavering,
Sorrowless, stainless and secure:
This, the Highest Blessing."
(-- the Mangala sutta)
Writing such a post certainly helps as well. May we all overcome whatever pain, and enjoy the highest blessing. Metta to all!