Apples and oranges. Vaccines are not anti-depressants, nor is there any evidence that they radically alter brain chemistry or have any suicide risk.
Vaccines can cause Brain Damage in rare cases. They can also cripple people in less rare cases. It would seem wise to find the cause. First step should be elimination of Three in One Vaccines and do the three shots spaced out individually. What can it hurt? Even my dog has adverse reactions to Three In One type vaccines.