No worries. Firstly, you are being honest with yourself. Secondly, you've got some of the causes identified already. Thirdly: > Just a couple years ago... ...

No worries. Firstly, you are being honest with yourself. Secondly, you've got some of the causes identified already. Thirdly: > Just a couple years ago... ... that's a well-known phenomenon called: getting old. Fourthly: > I went back to the gym two weeks ago ... aaaand you're all set - just keep it up now. It doesn't matter if you bench 135lbs or 90lbs. Frankly, after a certain age it's one step forward two steps back, all the way. Just know: you'll be on a bit of a slope from now on. Observe that the work you put into it is still paying off anyhow. It's encouraging, ain't it? Best of luck to you.