David you need hard work an intelligent training plan, you could stand to improve in both these areas. If constantly get injured it is likely related to one or more of factors, improper footwear, bad recovery, running form, nutrition, constantly, running on hard surfaces. You don't seem like you have studied why you get injured,nor do you seem to have the dedication to improve. You need to work around your problems, train smarter. Results take years of hard work they wont come instantly.
To avoid injury, Id recommend building up mileage on a soft surface like the grass or a dirt trail.Also check your form if you are not using your glutes and upper leg muscles to power your running , lower leg muscles become over worked and injured. It also may be that your hips are weak, this leads to excess pressure on the ankle and knee joint.