Help in translating a few lines taken from a magazine

Hi,
Any assistance in solving these mind-stumping problems would be deeply appreciated.

How does the ni after "doku ni" function. Is an adverb? agent? Just doesn't seem to make sense to me.
Same with "seifu ni". Does it literally mean "to" in this case.
I'm still a little rough when it comes to reading textbook explanations that are written in
Japanese. So please, if there are replies, it would be nice if there were a bit of english somewhere: relief.
Thanks.

(The subject ga) doku ni kurushinda.
(The subject ga) seifu ni tachimukatta.

"Ni" indicates the target the subject suffered from and the target the subject fought against, respectively.