This is a click bait situation. I am commenting contrary to my usual sense of keeping quite in such stories. Not sure but based on what you wrote, you seem to be a good person and should not be taken advantage of. First off, good that you ran into some fortune. I will just put some points so that you dont get confused with finance and other stuff:
Forget about bf. Is he going to be your husband? In that case, he can share the pie else nothing. Even in the case he becomes your husband, make sure that you are together and he is not in the marriage just for money.
Forget about relatives. It is your money. It is not their right to take it.
First pay taxes. Get an accountant and pay off the advance taxes. Keep additional money in a savings account with a local bank so that if there are more taxes you could pay them.
Based on what you wrote, maybe you have some financial savvy to capture to. So for now, I Would say just keep your local bank, a credit union, a chase or bank of america or citi assuming you are in US which you seem to be, as well as well known big companies such as Vanguard.
Pay off ALL debts, buy a home that you are comfortable with, split money into 25k chunk and put it in CDs in above banks, maybe take one 25k and offer to your mother/father/brother/sister .. at max. 25k .. you are free to give them just 5k or 10k based on what you are comfortable.
Put 25k in a 1 year CD - mark it as travel fund for that vacation to South East Asia. It really is a beautiful place.
After all this, you wont have much left. But if you do put them in some good stock funds or bond funds or if you are not sure stick with CD.
A big problem is not finance. It is dealing with nosy people. First you should not have told them as this is private. And if you did, you can say that govt. took it back in taxes. That you have joined the tea party now.
I cannot say how important is this. DO NOT GIVE MONEY TO ANYONE. Least of all that grandma of yours. I dont have anything against anyone. But if you want to give money, give it to charity. There are tons of innocent kids out there.. no fault of them and they are in hunger, poverty .. you name it. It is not your problem to solve it or you cannot solve it 100% but hey, you ran into good fortune .. it was not hard earned money. Rather than giving it to relatives, might as well give it it to those kids. If nothing, they will have some good days with tummy full.
Read point 9 again. That is pretty much the gist.