The opening is important because even if you have strong tactics if you find yourself in a poor position because of doing poorly in the opening, by then you may be at such a disadvantage that your strong tactics just can't get off the ground.
I am a reasonably decent player, perhaps a smidgin about average. If it might help, I would be willing to play unrated games with you and to tell you what I have observed about your openings and to make suggestions. Hopefully playing unrated games might give you ease from that feeling of your life being on the line. The rule on this site is that people can only be guillotined for losing rated games :-)
. I'd especially reccomend the immortal game since it tell history along with the story of the immortal game which is educational and fun.
You can't learn all things at once. Focus your attention onto a specific aspect of your game. This stops thing seeming too large or overwhelming. Also, as already mentioned, with openings learn the fundamental ideas, rather than worrying about move order. You could spend a while learning an opening, but if you are playing against folk that are also beginners they probably don't know openings either.
My biggest problem when starting out was not paying attention to my opponents moves-always think, why did they do that? then, don't assume that they are right, look at there plan and decide if it really is a threat, then respond accordingly.
The games that I have lost,the ones that really hurt, are the ones that I learnt the most from. Couple peices up and then caught by a backrank mate, oh, surely everyones had that.