I don't get homesick per se, but there are times if I am watching a movie or a programme on tv and it is set in the area I used to live, that I get a feeling of nostalgia. I first came to Australia in 2004, and have been back to UK 5 times since then. Each time I enjoyed my visit there, but was very happy to return to Australia at the end of each visit.
My wife is also English, (we met and married in Australia when we both had PR) and she does get homesick now and again. She says she never knows when it will hit her, or what starts it off, but over the past 10 years she says it has reduced considerably and she is always very happy to return to Australia as she considers this her home now. Mind you, she still has family in UK, whereas I don't, so maybe that has something to do with it.