Whatever happened to that unarmed manual that was on here? All you have to do is fight smart. Whenever I read recommendations on how you have to pretrain your every defensive skill with hours of unchallenging, unfun routine before you can grow a pair and just go adventure, I'm reminded of when I started in a city as an outsider and ran into a rampaging vampire before I could even reach the nearest warehouse. I used everything in that handbook to survive, and with nothing but a copper dagger against a faster, stronger opponent, it was all I needed (didn't use the spear because it doesn't dismember as well.)
Use patience, timing and observation. Keep the one-tick key under one hand and use the attack key to see what your opponent is doing. Until you get your observation and speed high enough, do less attacking, more observing and dodging. Don't attack when it isn't advantageous, and don't take the exclamation point to be the best guide to when that is. Because your opponents autoattack, they will attack at every opportunity whether advantageous or not, and you can exploit this to your advantage. Emulating them is what gets your companions killed.
When you're able to predict your opponent's attack, continue to defend and watch how soon their followup attack is. Use attack key to check their combat pose, whether they're recovering from last attack, or starting another, or that 1 tick between which shows no message. When you get a feel for their attack and recovery time, you can make better judgments on when you can most safely land attacks. Just doing this will improve your survival skills and attributes.
Counter the attack: Even if you have a shield, your best counter is to strike what they're striking with. For example, if they strike with a left punch or a weapon wielded in the left hand, hit that hand with one of your quicker attacks. Doesn't matter if it's an impossible attack, it will still deflect the strike. If you have a free hand you could also grab with it, but be sure to dodge before it lands so that you disengage in the same tick and aren't locked in place next turn. Doing these naturally improve your offensive skills until you can confidently disarm attacks.