Although shopping is meant to be my stress-reliever, I actually end up feeling empty when the amount of stuff I have in my room increases. That's why I try not to increase my belongings.
ご質問ありがとうございます。
"Although shopping is meant to be my stress-reliever"=「買い物をすることはストレス発散になるはずなのに」
"I actually end up feeling empty when the amount of stuff I have in my room increases."=「自分の部屋の物が増えると、実際、虚しい気持ちになってしまう」
"That's why I try not to increase my belongings."=「なので、私は自分の所有物を増やさないようにしている。」
ご参考に!