My Dear You have to go about this with wisdom..I wont blame you for giving him money cause that was the best decision you had to make. I wont judge you at all..
Please I believe so much in savings, save very well and please this is the time to inconvenience yourself..Reduce the aso-ebi and travelling cost and all unnecessary expenditure. Try and give your aunt monthly stipends for feeding like at least 5k or as your pocket reach, just make attempts to leave them behind without further friction amongst you, your Uncle and Aunty..Help them with house chores no matter how little before you go to work..Dont see it as suffering, see it as ''training'' to make yourself a better person.
Make sure you notify your Uncle and Aunty that you want to travel and you have to go..If they throw away your things fine, or try and get someone your uncle respects to come intervene...
In conclusion, Make sure you dont leave with bitterness and bad blood, no matter how they have treated you, they are still your family and u cant change that.. Show them love in all and in the future, you will better understand how to treat people with similar situatio