Context: I'm 30, my parents are in their mid 50s, they are divorced and they both married after. I don't live with any of them (I'm in another city) and I visit them about once a month, also for special days like holidays.
The long story: I want really bad to live abroad (in another continent) in the near future, the reason is because I want a change in my life, I want to live new experiences, visit new places, have a better life quality (I live in a third world country with lots of issues to achieve that).
I haven't talked about this with my mum but I know she will support me and be happy for me, but with my dad is a whole other story. He is married to a divorced woman with a son that, a couple of years ago, left home in bad terms, mainly because she was overprotective and he was a big boy already, so bottom line there is still a lot of abandonment sentiment going around the house and this also made her see me like her own son more than ever, is worth adding she also has very delicate health, and any kind of sadness express in her body in the form of illness.
My dad suffered from depression a couple of years ago, with the fortunate coincidence that when he was on his worst days I was on a 3 week trip across europe, and in those days not only I was very far away but I didn't know what to do to help in that position, so I didn't talk to him much when he was really sad, and I didn't want to go back in the middle of the trip because I thought it wouldn't make a difference in his illness besides having my company through his rough time. Obviously I felt very guilty about this, and I apologized to him and we both left this moment behind, but now I'm afraid this will bring up the ghost of the past. Besides this episode I know this would be very difficult for him, because I'm his only son, and he doesn't have any close people besides his wife so I'm a big part in his life and it would hurt like hell to have me too far away.
What I need help with: I want help in how to approach them in the best way considering that the situation is more than delicate. Also I don't want to create false expectations related to for how long I'd be out, because I don't really know that, today I think about a couple of years, but I'm very aware of the possibility that I might don't want to go back at all. Also I'm not just thinking about "the talk" but when to have it (right know I didn't even started planning this) and what else to do to live this process as painless as possible.