I know I want to ctb, any time I get close I seem to get scared and don'tgo through with it.
I certainly understand that, probably the main reason I effed up previous attempts to CtB, but I'd still suggest that might mean you're not ready, that on some level you think there's still hope, that you can still be helped. As much as I regret not dying months or years or decades ago, thinking back on it, I did still think there was something I hadn't tried that might make life bearable. Of course, I've since tried all that, and no joy, but I wasn't completely certain at the time, and I think that held me back.
Unfortunatly theres no bridges over 50 metres in Scotland
A quick Google search on vertical clearance for bridges in Scotland suggests the same thing. Like I said, though, you definitely don't want a non-fatal fall, so... I'd suggest that jumping off a bridge is not a good idea in your case, unless you can travel outside of the UK and can actually go through with it.