心境にする=put in a state of mind, 複雑な心境にさせられる=be put in a complicated state of mind

1.
かしそこで礼を重んじ作法を尊ぶ、それが人を信じ助け合う心境にする。
However, we respect and respect our manners, which makes us believe in and help each other.
*それが...心境にする
 That puts us in a state of mind that...

2.
二人の結末を知っている身としては実に複雑な心境にさせられる遣り取りです。
As a person who knows the ending of the two people, it is an exchange that makes me feel very complicated feelings.
*複雑な心境にさせられる=be put in a complicated state of mind

3.
あれから家内も寺に参じまして早速に拝顔いたしましたが、余りにも娘の面影が生きているに心休まる心境にしてくれます。
From then on, my family went to the temple and immediately came to see me, but my daughter's image was so alive that it made me feel at home.
*娘の面影が...心休まる心境にしてくれます
 My daughter's face put my in state of mind of feeling relaxed