How do I include a custom fieldtype by default in every form?

I have a custom fieldtype but I dont want the user to have the option to add or exclude therefore I want to automatically include via the Form.cshtml to include the fieldtype.

Any example of how this can be done?

I've instantiated a new FieldType and created new FieldViewModel, FieldsetViewModel and FieldsetContainerViewModel so I have the field displayed in the form.

The only thing is when the form is submitted it doesnt fire the ValidateField for the fieldtype.