After scoring twin tons to honour Hughes, who died in November after being hit by a ball in a Sheffield Shield match, Warner said he did not want to play in the rescheduled first Test in Adelaide.
Warner was among those present when Hughes, batting for South Australia, was felled at the SCG, with Brad Haddin and Nathan Lyon among the other Australian Test players representing New South Wales.
The attacking opener said his mind will wander to 26-Test representative Hughes any time he takes centre.
"If he could just see the support he had and the impact he had here in Australia and around the world, he'd be so embarrassed and I'd like to thank everyone for their support and messages," Warner wrote in the Daily Telegraph.
"The days leading into the funeral were just as tough. I didn't even want to pick up a cricket bat.
"I spent almost nine hours on the golf course and at the driving range the day after Hughesy died, just contemplating what was going to happen to myself.
"I have a little baby girl, Ivy, and every time I walk out to the middle, it will hit me.
"No parent should think their son or daughter is going to go before them, let alone see it happen.
"My first net session back I had a hit with my batting coach Trent Woodhill in Sydney and I couldn't have hit them any worse."
Warner said he eventually decided to play the series opener "and do it for my mate".
"My Test debut was with Hughesy, and taking that spot in the nets where he could have been at the same training session felt so hard," he said.
"I walked in there and faced half a dozen balls and I walked straight out. I was in no state to do it.
"There were serious thoughts there about pulling out of the Test; I didn't want to play.
"But in the end my emotions took over and I said I have to get out there and do it for my mate."
Nathan Lyon, traditional leader of Australia's victory song 'Under the Southern Cross I stand', stood side-by-side with his team-mates, as they celebrated the emotional 48-run victory on Saturday.
"It was quite emotional for Nathan Lyon, who sings our team song," Warner continued.
"He would usually stand in the middle but we didn't want to have anyone in the middle because that spot was for Hughesy.
"He was our 13th man and we felt like he was the one who deserved to lead the song.
"He's always going to be in our memories.
"I know from now on, whenever I get to 63, it will be nerve wracking, but I will raise my bat to the sky."