Recently, I had been feeling at a dead end with my English learning.
But after I started using the English-English dictionary, I've come to enjoy learning English once again.
This is because I feel less confused with the process of translating from Japanese to English and vice versa, and also it is less work.
ご質問ありがとうございます。
"Recently, I had been feeling at a dead end with my English learning."＝「最近、私の英語学習で限界を感じていました。」
"But after I started using the English-English dictionary,"＝「でも、英英辞典を使い始めてから」
"I've come to enjoy learning English once again."＝「英語学習がまた楽しくなりました。」
"This is because I feel less confused with the process of translating from Japanese to English and vice versa, and also it is less work."＝「これはなぜかというと、日本語から英語に訳す、そしてその反対をすることによる混乱と労力が減ったと感じるからです。」
ご参考に。
アメリカ合衆国 
