The former Love Island host, who died aged 40, was laid to rest on 10 March in a private ceremony attended by friends and relatives.
Lewis said he had never imagined he would be unable to ever speak to her again in an Instagram post shared on Monday.
“It’s already been a month I love and miss you so much, I never thought that one day I will never be able to see or speak to you again,” he wrote.
“I wake up and think you’re going to be laying next to me or you’re going to call me in a minute. It just doesn’t seem real.
“I wish I could give you a kiss and a cuddle and say everything is going to be ok. I am so grateful I met you I just want to make you proud.”
Caroline stepped down from hosting the first ever winter series of Love Island after she was charged with assault following an alleged row with Lewis at the flat they shared in London.
She was on bail and awaiting trial due begin on 4 March after pleading not guilty to charges of assault by beating.
The former X Factor host previously said of the incident: “While matters were not as have been reported, I am committed to cooperating with the appropriate authorities and I can’t comment further on these matters until the legal process is over.”
After the initial court hearing, Lewis insisted he was not assaulted by the presenter.
“What I witnessed today was horrible,” he said. “She did not hit me with a lamp. Arguments do happen every day in every relationship. Gutted I am not allowed to protect her right now.”
Following her death, Caroline’s management blasted the Crown Prosecution Service in a strongly-worded statement.
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