First, OP, try not to worry too much, I know it's hard (I remember the despair I felt initially and still do sometimes ) but it's worth remembering that the most important thing is that your child makes it to adulthood happy and whole emotionally. Trying to get the balance between doing enough for your DC without crippling them with too much pressure is hard but key - an unhappy child won't learn anything. Don't do doom and gloom with him ("this is terrible, you have to learn" etc) but calmly keep at it. At the same time you have to maximise his strengths, whatever they are because his self-confidence will be taking a daily kicking at school! So try and look for the things he enjoys and put plenty of time into them be it sport, art, music, drama etc
With regards to sorting the reading itself, whatever "therapies" people might recommend to you and you chose to follow, please don't assume that school can't help because they can! Force them to give you as much support as possible - he's at school 6 hours a day so he needs to be engaged with the curriculum even if his reading and writing holds him back to some extent. Also, no matter what else you try you MUST give him a solid grounding in phonics, becaus it gives him the tools to be able to learn to read. The "sound foundations" series are good for you to do at home with him. I've had positive experiences with tutoring from Dyslexia Action too.
On a final very long winded note do consider specialist provision, for many very dyslexic children it's the only way they survive emotionally, especially in their teens.
Most importantly, keep loving your boy - the best thing anyone ever said to me was "love the child you've got, not the one you wish you'd had". It's important they know we value them exactly as they are!