The DJ, who was well known for his appearances on the Ellen Show, died from apparent suicide on Tuesday morning, it was reported.
Comedian Ellen, 64, has vowed to "remember all the love" Stephen brought as she shared a video of her favourite moments with the star.
Sharing the clip on Twitter, Ellen wrote: "Right now what I want to do is remember all the love and laughter I had with tWitch.
"He brought so much joy to my life. I know he brought joy to yours too. I’m going to be sharing some of my favorite moments with him."
She encouraged fans to also post their memories and added: "#ILovetWitch."
The throwback video started with a clip from the Ellen Show as the host said: "I'm supposed to be throwing to a montage right now of some of our favourite celebrity moments, but I'm not going to do that.
"Over a decade ago, I met someone who changed my life and our show. And I'm talking about you tWitch."
Stephen seemed overwhelmed by the gesture, with Ellen adding: "I love you so much."
The video then cut to Ellen being asked by someone off camera what she would like to say to tWitch, in a moment filmed for Ellen's final series of The Ellen DeGeneres Show.
She replied: "Well, I don't want to say goodbye."
Ellen and Stephen first met when he taught her how to dance for the Ellen DeGeneres Show.
"He was so patient with me. That was my initial love for him, we just bonded over learning to dance together," Ellen said.
Fans seemed to love the addition of Stephen to the programme, with the video showing him having fun and dancing with members of the talk show audience.
"Whenever he's not here, for whatever reason, it's just different. I mean, I count on him to look over at and make silly jokes. He's my pal, you know, he's my sidekick.
"We have this connection, so just looking over and he makes me laugh. He really, really makes me laugh.
"I love you tWitch and you know how much, we tell each other that every day. When we say goodbye after the show, we both say love you. He says love you much and I say love you," Ellen said.
Tearing up, she added: "He's never going to be out of my life. He's always a part of my life."
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