I don't want to be seen to be preaching from the pulpit but I have had similar thoughts (non BA but fly for a legacy carrier) but disconnecting from work when the parking brake is set is paramount. Whilst feeling fulfilled at work certainly helps, it is not the key to overall fulfillment and populating your spare time with meaningful tasks that make you happy, can go a long way to offsetting any grumbles at work. As pilots, we still love flying but it is very easy to let workplace politics affect our enjoyment. If you can afford to go part-time then grab it with both hands.