Your traffic takes an interesting route, especially since it does not have to..(There may be reasons the relevant ISP's are using this route though) It leaves SA, breaking out in India, where it has another hop in India before going to Singapore.. This where it gets interesting.. Instead of going to the destination(singtel.com) which appears to be in Singapore, it goes to Hong Kong for 3 hops and then goes back down to Singapore for another 5 or so hops before finally reaching the destination..
So, instead of having a latency of about 200ms, you are getting 380ms.. That much latency is always going to provide a crappy experience and delaying every interaction.. That said, this traceroute is to singtel.com and I imagine this is not where your wife is doing her work, so her traffic may take a completely different route than this one here..
If you did your speedtest to the singtel server, I am not surprised it is that slow based on that route it is taking..