Settling Alignment Differences

[Gale]

I'm wondering how to go about dealing with another party member who is of an entirely different alignment. For context we're a level 5 party and my character is a Lawful Good Crusader; the other player character is a Chaotic Evil Cleric/Wizard. Normally, I would feign ignorance but it was practically impossible since the PC was all but shouting out "Look at me, I'm evil." Eventually, I decided to threaten the character that I would kill her if she didn't stop being absurdly evil. That's when I was told out-of-character that she actually has a lighting spell that does 15d6 damage that would effectively one-hit kill my character. Apparently, it's a homebrew--I'm guessing from dandwiki (http://www.dandwiki.com/wiki/Main_Page). Needless to say I backed off immediately.
My goal isn't to find a way to wipe the character out. (Although, that would be nice.) I'm actually looking for a way to simply prevent her from stepping all over the group if she decides to go renegade or potentially attacks me because I'm not letting her be evil.
I'm also wondering if anyone has any ideas as to how we can work together in a party and not be down each others throats constantly. The players himself is actually a nice person who I'm friends with, but I can't ignore the fact that his character is blatantly evil in terms of role-playing. I'm seriously stumped to find any reason why we would actually be cooperating.

[Honest Tiefling]

Have you approached the player about the problem? I imagine that a reasonable and nice person could be persuaded to tweak both of your characters to work...Decently together. Perhaps there is a larger evil out there, and your lawful good crusader can be depended upon to not turn to to it, and his character would find it more amusing to not kill...But corrupt your character. Your character might be stuck as they might be one of the few mages willing to work against this problem. I'd also speak with the DM if they have any suggestions.

[LTwerewolf]

Character interaction shouldn't be thought of as alignment problems, but more as player problems. Decide which character isn't meshing with the group as a whole, and that player needs to change something. Also make sure you get yourself immunity to lightning or the ability to reflect it back at them. What level are you?

Also there's no excuse for one player to have ridiculously overpowered abilities from a homebrew class unless everyone gets the same.