Someone who knows what it’s like can probably get through to him. My brother got through to me because he knows what I’ve been through and I know where he’s been – he told me things he wasn’t aware I even listened to, and I heard.
Everyone needs something we can’t do for ourselves. We don’t have the power we need, to comfort and heal ourselves. But Someone made us and He watches and cares. It doesn’t always seem possible but He is healing us all along, as much as we allow Him to. It’s in our hands how much to let God do and how much to place ourselves in His hands. He loves us all. But there’s an expectation with His love, not to meet a standard that’s out of reach, but to pass that love and care on. It’s inseparable, giving and getting that mercy and healing and caring. If you won’t give it, you can’t get it either. It goes together. So some people are without love and mercy, but God didn’t make them that way and He won’t leave you in their hands forever no matter what it looks like. This world is the waiting room to a life much longer and just as real, and God will keep you if you give yourself to Him, and He will leave you alone if you avoid Him. He’s the one to keep an eye on. What other people do is out of your hands and only temporary anyway. If someone abuses you they’re hurting their own soul, not yours, and God is protecting you as much as you ask Him to, spiritually and sometimes even physically and psychologically. The abusers are the ones destroying their own souls, which they’ll be stuck with for eternity. But they can ask God’s mercy too. It’s up to them. And if they will learn to love He will have mercy.
That’s how I would probably start.