The actor recently confirmed that he will be leaving the soap as Christian Clarke, along with his on-screen lover Syed Masood, played by Marc Elliott.
He explained that filming his final scenes on the BBC soap was "exhausting".
"Leaving was incredibly emotional, and the last day was very difficult," he told What's on TV.
"You have the whole anticipation of it coming and, when it finally happens, it's overwhelming. I was in tears; our executive producer, Lorraine Newman, was in tears; the people in props were in tears. Afterwards, I felt exhausted."
Partridge stated that his decision to quit the soap was a joint one with co-star Elliott, as he felt the characters would not work well on their own.
"Christian and Syed are a unit. I know some characters can survive having their other half leave but, for me personally, I didn't see a future for Christian without Syed," he explained.
"It was very much a joint decision and it wasn't an easy one for me to make but, at the same time, you have to serve the story and there has to be a professional happiness tied into that. In reality, I think I would've been slightly redundant without Marc."
On his overall experience on starring in EastEnders, he added: "I have had the most amazing time, and it's one of those jobs that I will hold dear. My memories will be kept in my heart - and I mean that most sincerely."
Partridge and Elliott will leave EastEnders next month in a dramatic storyline.