The key things is not to look at the symptoms (anxiety/ torments) but rather seek the cause. I find it useful to the do the following. Start systematically asking God what allowed the devil authority to torment you. Ask God to convict you of anything that you have done or said or yielded to mentally (teaching you have believed) that has given him authority against you. Keep praying this systematically each day. (Take notes about what you feel or think about as you pray and wait on God for conviction. Bear in mind these can be very unrelated to the symptoms you have. Just be open to the Spirit of God. Once you start to build a picture, the timing, the cause, it will generally require some sort of repentance, forgiveness or renouncement of things of the past. This is the key part. By confessing & renouncing we destroy the devil's authority. Thereafter you have the legitimate right to command the devil to leave you alone. Continually prophesy restoration over your life, proclaim your deliverance, stand on God's faithfulness in faith. The devil has lost his power to hold you in affliction and when he gets the message that you are on God's strength, trusting in his faithfulness he will leave. Just be persistent, consistent and you will get the victory.