What is the meaning of to 'gain one's ends'?
Solution 1:
The passage must have been translated from the German, probably some time ago.
End in this context is an old-fashioned term for a purpose or objective. I suppose the meaning is that, if you wait until you can achieve your purpose through love, you may have to wait a long time (sunny days not always being common in northern Europe) and life is too short to wait.