Recurring chest muscle strain keeps coming back. what do you suggest?

Physical Therapy: Have you seen a therapist? If you have not, they can be a great resource that is relatively inexpensive. They could perform a deep tissue massage coupled with stim and ultrasound that can serve to improve your symptoms. Ice and activity modification along with a nonsteroidal anti-inflammatory may help as well. Consult your local ortho for eval and prescriptions.