Upvote:2
Or is our case too complicated to even try without lawyer assistance?
There may be quite a few hurdles to overcome, what with previous marriage, immigrant intent (settlement), refusals, failed appeals. If you were a minor at the time, you may be less impacted, but your mother's UK immigration record would be of greater concern.
The UK regulates and registers those legally able to give immigration advice and services (advisers, solicitors, barristers and members of approved professional bodies). Here are tools to get you started: