I'll start my story by saying that sometimes a spirit is the only way you'll be able to cope.
Last year my sister (I'll call her Dawn out of respect for the deceased) unexpectedly and very quickly passed away on November 8th at 1:22 in the morning. She was a very hard-headed woman. We weren't on speaking terms when she died and it still eats me up.
The day after she died, I took a bunch of 50mg Melatonin, and eventually cried myself to sleep. Then the first dream happened. I was dreaming I was in my buddy's house at the bottom of his steps, and my sister walks down and just looked at me. Keep in mind I am an Atheist so I have no idea why I asked her this, but I looked back at her and asked "Did you get into heaven?". "Yes", she replied. Then I woke up.
Fast forward about a week, and it's the night before her funeral. I dreamt I was at my girlfriend's mother's house, and for some reason the main door is opened, but the screen door is shut. Anyways I'm looking outside, and a white Durango pulled in the driveway. Out of the passenger seat steps Dawn.
"Hey that's my sister!", I screamed excitedly as I ran outside. She greeted me on the porch, and we both stand there for a second. I broke my silence and said, "wait a minute. Dawn, you died". "I know", she said as she pulled me to her and hugged me. It felt EXACTLY like my sister's hugs. Then I woke up.
Fast forward another month or so and I'm at my dad's to stay the night. We all go to bed (them in their room and me on a couch in the living room), and I wake up 3 or 4 times. The fourth time I woke up I was agitated so I sat in dad's chair which is directly across the room from the tv. I turned on my dad's lantern so I didn't have to sit in pure darkness, and it won't disturb them. I lit a cigarette, and looked at the tv.
There, staring back at me plain as day, is my sister's face. I could see her moving her mouth, but the words weren't coming from her face but yet inside my head. All I can hear over and over is "I'm ok, don't worry". Then her face faded away.
I had been trying to get the guts to off myself for weeks. That incident kept me from doing so. I haven't seen her since.
Over the next couple of years after that, however, my Mamaw stated several occurrences where she said she had spoken to him. She often hid it but it was obvious she was sad and lonely. They were married for more than 50 years. Shortly before she died in a car accident, she stated that she talked to him in a dream and he said that he would see her again soon. It was kind of eerie.
As far as your last sentence I do agree with everyone else and think you should seek some counseling. Killing yourself is never the answer. Life is a gift with many blessings and I'm sure your sister would not want you to do that. God bless