Hi Trevor,
A bit more information would be helpful.
1. How do you get the bike back home?
2. Do you put the battery on charge every time you get home? If you do, do you disconnect the bike's battery leads?
In the meantime, you can perform this basic battery load test; it assumes a roughly standard Ah battery and headlight consumption (i.e. no miniscule gel cells or 100W filaments

):-
A. Measure the voltage across the battery terminals (I'm assuming you've a voltmeter or multimeter?) - if it's much below 13V, charge the battery up first.
B. With the battery ideally showing something above 13V on the meter, turn on the ignition key switch,
don't start the engine (turn the kill switch off if you want) but turn on the headlight (ideally main beam).
C. Leave the headlight on for two minutes, watching the meter that you've left connected across the battery terminals. If the meter reading doesn't drop appreciably in those two minutes, the battery is probably ok (although you can have it fully-tested for peace-of-mind). If the meter reading does drop appreciably in those two minutes, the battery is almost certainly 'creamed'.
Bear in mind though that a knackered battery doesn't preclude the possibility of an intermittently-faulty (brought on by vibration and/or movement) supply or earth connection, which was my other immediate thought.
Let us know how you get on.
Hth.
Regards,