What can i do to stop feeling really guilty for having a mental illness when there are so many struggling with physical illnesses ?

Mental illness: There is much more of a social stigma about having a mental illness, and having a physical illness. Ask yourself, did you choose to have the mental illness, whatever it may be? Chances are the answer is no, much like the person with physical illness. Shame can be huge for people. Discuss it with a reputable psychotherapist.

Mental illness: Accept yourself for who you are, not what you are, keep a good support system for advise and guidance, and work with a therapist to help you build on your strengths instead of magnifying your weaknesses.

Guilt is depression: Please read the other responses as they may be helpful. I recommend that you interpret your guilt as a symptom of depression. Part of being depressed is often feeling unworthy of help. Thinking you deserve help less than anyone else is your low self-esteem and not reality. Reach out to the physically disabled through volunteer work if you want to help but don't punish yourself with guilt.