I know how to eat right and know i'll develop diabetes soon but can't change my ways, what do I do?

Adiction. Food is like an addicion, and awareness of the adiction is the first step. You seem to have already stepped in the right direction. Diets and plans only go so far which you may have already guessed. Food addiction requires change at the psychological level. Treatment with some one who specializes in behavioral, psychological domains and nutrition would be the best way to approach this issue.
Get help. There seems to be a disconnect with your emotional health and physical health. Getting help with why you are having this block will be critical in preventing future complications. Everything is connected so understand what are your emotional roadblocks to improving health.
Get uncomfortable. There is a part of your brain that wakes up before you do, and it wants to do what it did yesterday, like an air conditioner setting. There is another part of your brain that makes decisions all day long. Make a plan, become uncomfortable, work your plan, all day long. Dont go by motivation. After 3 months, losing 1-2 lb/week, you'll feel better. My website www.Familyhealth.Pro has more tips.
Take small steps. Start with small changes/goals, and focus on one bad habit at a time. Gradually increase your exercise instead of jumping right into a vigorous program. Get a new cookbook with healthy recipes or consider going to a dietitian. Give yourself healthy rewards for meeting your goals. You probably do a lot for others, but it is time to make yourself (and your health) a higher priority. You can do it!
Do you really know? The mds so far have given you very good advice but this is on the assumption you really do know how to eat. Hunger occurs when blood sugar drops to a critical level. Brain and heart demand sugar. Non-insulin diabetics and non diabetics jet out Insulin when carbos and large meals are eaten. Sugar crashes, vital organs screem foul and you eat. Small frequent eating, low carbos, exercise - surprise!
Talk to someone. It might be helpful to talk to a counsellor or therapist to try to find out why you are unable to change your eating habits. Adding exercise may be a good way to start.
Social/psych support. If you know what to do but won't or can't do it, then this is a motivation/stimulus control problem. Psychological evaluation might be helpful to you. Social support group could also give you the drive to change.
Change your mind. I agree with the answers listed so far. Please keep in mind that someone who is convinced that he or she cannot change tends not to change. The first step is to accept that change is possible, and it is indeed possible.