Don't feel like you have to justify yourself or your feelings to anyone. How you feel is how you feel. Part of healing is being able to own those feelings and work through them
Not justifying just explaining the difference.
I own my feeling of failing my babies and I am sure the feeling will fade as time goes on but while they both still have problems from their very early births the feeling of guilt and failure is ever present.

I am thankful every day that they are here and for the most part healthy and am glad I could carry them far enough to give them a fighting chance but it does not mean that my feelings of failure/guilt are not valid and to have these feeling in no way makes you less grateful for what you have.