There's plenty of women with young children driving trains on the railway, though you in terms of lifestyle you need to consider the following:
During the early stages of training you'll be spending approx. 8am-4pm in a classroom (the exact times may vary though these hours are typical), when you get home you'll be spending your time revising the topics you've learned about so you can pass various written and practical examinations.
During the latter stages of training, you'll be following the shift pattern of your Driver Instructor, the earliest time you'll start on early shift is shortly after 3am, the latest time you'll finish a late shift is around 2am, you'll need to make sure you have adequate sleep.
Once you are qualified, you may be able to swap to a permanent early or late shift by swapping with a colleague who wants the opposite shift to yourself, this is not guaranteed.
If you want to leave after qualifying, you may well be expected to repay some of the costs of your training, Southeastern will provide you with more details of this.