Another thought, just from the people pleasing emotional aspect of things. If you take some time to get setup with a financial advisor & get some investments going you could set something up where the interest/dividends/earnings/etc... Goes to help your relatives. Basically you'll still be helping them, but with a steady stream of $ that comes to them over time instead of getting a huge lump sum that they will blow pretty quickly. It might also buy you some time in the emotional range with them so everyone's not so angry at you. Basically say 'I'm meeting with a financial advisor to see if I can setup some kind of investment that would generate some steady income long term for the whole family'. This JUST happened, what you really need right now is time & perspective & advice before you blow everything.
Also can you talk to the lottery commission, or whoever & see what the distribution options are? Sometimes you can get it all in a lump sum, but you get charged a 10% fee because you get it all at once. OR you can get it paid out X amount a month & get the full amount over 20 years or whatever. Here's the thing. Option 2 means you get more money in the long term AND you can't blow it all with a few bad decisions.
IF you don't get option 2 & can only get the money in one lump sum, you can always setup a bank account that generates interest & puts you on a salary every month. The absolute big simplest way to do this is get 2 bank accounts. One savings, one checking. Dump the big lump sum into the savings account. Setup a transfer of X amount every month to the checking account. Forget the savings account is there & ONLY spend out of the checking account. WAIT 6 mths before you so anything else. Adjust to not being dog poor, give $ out of that checking account to family as you want, hire a financial person, learn about finances. Then in 6 mths even if you've blown everything in the checking account every month you've only blown a small % of your total $.
Good luck, this shits hard! I hope your family rally's to support you soon.