We know what his form was like at Chelsea but the injury problems that plagued him at Madrid completely ruined his career. When we talk about respect of course it has to be, but indeed the condition he is in right now doesn't really reflect a good player especially his career is over now.
Yes I heard he had a lot of injuries. I thought he was also still injured at this time. But it turned out that he didn't get playing minutes because Anceloti didn't seem to believe in his performance. Reportedly Anceloti and Hazard don't talk to each other either, and maybe that's what hasn't played much minutes this season. It looks like Hazard is going through a difficult time this season with Anceloti, his contract will also run out another year. It is likely that Real Will also not let him go on a free transfer.
Modern football is very stressful, you play a lot, indeed you play too much
it's obvious that if you don't have adequate athletic training you'll break
if you're too old, you break (see Benzema)
if you happen to push too hard, you break
only coaches with a large squad and good turnover manage to do well throughout the season