It does not follow from the definition of suicide that responsibility lies solely with the victim.

The responsibility for any act lies with the person who committed it. I think you can work out the rest of the syllogism from there.

Death is not an act, it's a consequence. So even if we accept that a person cannot bear any responsibility for someone else's actions, they can still bear responsibility for the consequences. The premise that a person bears sole responsibility for the consequences of their actions is untenable as no consequence has a single cause.

You're equivocating.

No.