I was raised Catholic and gave it all up aged 12. Even at that age, it all seemed like so much nonsense to me. Declared myself an atheist much to the distress of my Mum.
In my 20's I read a lot about Buddhism. What I liked about it initially was that there was no belief in a monotheistic 'God', that they don't try and convert others and even the Buddha himself said that it was only a theory and encouraged others to be sceptical about everything.
Cutting a very long story short, I began researching my maternal Grandfather, who died quiet young of TB. There were too many silly coincidences, like his date of death being my birthday.
The 'ego' or 'self' is just a role we play in this life. I can't even begin to explain what persists between lives. I hesitate to call it a 'soul', it's just a bundle of desires that we carry between incarnations and we're bound going forward by our Karma via our actions, both good and bad.
I believe we also tend to reincarnate in 'soul groups'. When my Mum was dying of cancer, I confessed my belief to her that I was her Dad in a previous life, and she said 'I know'. When my son was born three years after she passed, he has a really irregular bump in his skull in the exact place that my Mum had her brain tumour.
I still remain an atheist.
In regards to Buddhism and suicide, I believe it's all about intention. If you're ctb'ing with the sole intention of hurting others, that's seriously screwed up Karma that you'll inherit on the next go-around.
But if you're doing it with the intention of ending the pain you're enduring with consideration of the pain that you'll cause others, then the universe gives you a pass.
Again, I approach the Buddhist model almost like a scientific theory. There is empirical evidence of it (Dr. Ian Stevenson's comprehensive work) and cases like James Linegar ()
That's just my 20 cents.