Help; I need information, type 1, diagnosed Dec. 22, 2009

I have been diagnosed with diabetes in Nov, and put on the pills, Metformin and they caused many promblems and then glipzides ER, I was devistated to know I had sugar promblems; but people who I talked to told me I can or will come off the pill in a year or two, ( none of them have diabetes only what they heard or new someone who it had happen for). I have been sick since August of 2009 and the doctors did not know at that time what was causing the promblems ( reacurring yeast infection, was all I went for) but I thought the every 15min. bathroom visit was because of the 3 cups of fluids I would drink which I said that was due to the summer heat which is soo much hotter then Chicago which I lived all my life up until I moved to Arkansas. ( July 15, 2009)
I am 5′ 4" and only weighed 150lbs.
I just found out Dec. 22, 2009 that I have type 1 diabetes and now is on insulin. and I don’t know what to do.
I wake up and my sugar is over 400, the highest it been so far is 454. I was told that I am to take the insulin when I eat and the other at bed time. I eat in the middle of the night almost every night ( sweets) have been for years. I am small framed and never had a good appetite for food. I can be hungry and not eat, I usally eat once a day and maybe some chips and pop some other times in the day. I have lost more weight and wish to gain it back, but when I eat more food I get diarreah for days. is there something I can do to stop the diarreah for good because over the counter drugs don’t seem to work like they use to before the diabetes. Imoodium A-D or Pepto. I want to know do I suppose to take the insulin when I eat the chips in the middle of the day or when I wake in the middle of the night and eat sweets; even after taking the bedtime shot, which I think suppose to bring my sugar down to 120 as my doctor said he wanted it to be.
I don’t understand how to do it if I eat after I take it when he said I should increase the dosage ever night till I wake up and my sugar is at 120.
I have sore muscles, I can’t sleep for more then an hour at a time and mostly up all night.
do my bedtime insulin still work if I am not able to sleep?
I know this is a lot, but I need all the help I can get. I have no one I know that is a diabetic. and I have been fighting depression since I learned I have disbetes and the sickness I am going through make me fell worse. exspecially since I have not been sick since I was 4 yrs. old. I don’t want to loose any more weight but don’t want to gain too much ( just what I lost already) so what can I eat to help with that? please anyone, any info will help.
may God bless you and all in your family for all the help you take out from your time to give me. may the Grace and Love of Christ Jesus be poured out upon you all.

Thank You; Cassandra B.K.A Cookie