Cullen, who was a key member of Hamilton's support team as his physio and assistant, departed from her role early in the season.
Her role is now split between two new physiotherapists, although much of Hamilton's support network remains the same behind the scenes.
Hamilton and Cullen remain in contact to plan "the next fun adventure", and the seven-time world champion added that he hoped they could potentially climb Mount Everest together in the future.
"I have a slightly different setup, [Angela's old] role is shared between two individuals," he explained.
"The rest of my team is the same. Ange and I was talking just the other day, we stay in contact quite consistently.
"We're always going to be in each other's lives, always looking forward to the next fun adventure, whether it be skydiving, whether it be climbing Mount Everest together at some stage, probably - who knows. And just continuing to support each other in our journeys.
"The setup I have right now is great. One of the guys - Steve-O - has been with me since my first race at McLaren, he also came here when I moved from McLaren to here as my gearbox technician. And then he's moved on to several different roles and he's helping me right now.
"Otherwise I'm working with someone on my training, she's here, Kylie. And then I have Santi here as well, I have Penni. I have a great support structure."
Source: Autosport