being faithful

i remember awhile back, @ SHINE fellowship one night, we were doing a bible study on first corinthians. chapter one verse nine reads "God is faithful, who has called you into fellowship with his Son, Jesus Christ our Lord."
obviously, i must be an immature christian who doesn't understand this passage @ all. because i'm having some trouble agreeing to that sentence.
'faithful' is defined as 'steadfast in allegiance'. i suppose that we're the ones that are supposed to be steadfast in allegiance to god, not the other way around.
but the one we remain steadfast to, shouldn't he in turn also be steadfast toward us?
that passage from first corinthians says that 'god is faithful', but i'm having some trouble figuring out why a god that is faithful would do to me what he did, i.e. give me a brain tumour and leave me bloody cripple.
why would a faithful god do that to me? wouldn't a faithful god look after me and keep me safe from any number of terrible physical afflictions?
i remember i used to ask god, what had i done that was so sinful that made him smite me down with a brain tumour. was it that i didn't pray enough? or didn't give enough offering? or didn't sing loud enough during service?
unsurprisingly, though, i never received an answer.
i guess all i can do is just keep persevering, keep struggling on, clinging onto the hope that one day, god will get bored of me and turn his wrath onto one of the 6 775 235 700 and leave me alone to recover the shattered shards of my life. and hell, am i ever looking forward to that day!
actually, correction: mother tells me that god IS faithful to me. "had He not been faithful to you, emily, you'd be six feet under by now." well, fair enough.
anyways, next post here ... the ekka day holiday? unless sth comes up before then. righteo, until then!
cheers,
em. ^