New to this just looking for help

Im 34 year old male been married since i was 21 and have 3 boys aged 12, 10 and 8. My life has been a roller coaster i was a drug addict since 16 up till 30 i was what you called functioning addict i have allways worked since i was 15 apart from 3 months as i was getting off the drugs and finely seeking help. I had tried to get help couple times before hand but would get shrugged of as i was married, had house, rental property and a car. As my wife has been with me the whole way she isnt and was never a addict she tried it once or twice when first met but once kids come along never again. So those 3 months where very hard times ( and next 4 years ) as for the first few weeks i was in bed because thats all i could manage to do. Then came all the counseling and medical appointments. So i have been diagnosed with few things but never really lasting too long on each medication as i hate the numb feeling they give you. So the main reason i writing on this forum as after battling my addiction and back in the workforce i now drink lots i do FIFO work so i dont really drink while im away but when im home its like i cant function without it. Then soon as i get back to work im in work mode. This time back i had a argument with my wife avout the drinking and then realisation kicked in i feel like i have just woken up at 34 with a family i didn't see grow up either because i was away working or on drugs/alcohol when home i dont remember all the great times i see in the photos and i feel very alone. I feel like i have been non stop creating hurt in the family. My wife is at breaking point and my kids are watching there dad slowly drown himself with alcohol. So last night while on night shift as i work alone it all hits me at once but i can handle it not the first time i have felt like this but i wake up today and its still there that feeling would the family be better without me so wrote my letter (suicide letter) this isnt first time i have thought about it i have been hospitalised when i first got of the drugs for trying to commit suicide but this is different that was a spare of the moment decision this has been whole day and more weighing up what would be better for my family or how do i let them know that i love them but this would be best for both parties. Not to mention how did i just miss 34 years of my anyway missed out on the kids growing up and have hurt my wife that much that now she is unhappy. Is anyone else feeling the same or had same feelings