I have 3 paths for you:
A fast solution is to dump dex and max both str & con, so you can have an higher fortitude, wich is the main defence against stuns usually. Since you are using full attacks all day the low dex will not wither too much your dmg. And remember to eat something, so you can have other +2 to str & con, so other +8 to fortitude, wich is more or less what bear fortitude talent gives you.
The alternative can be just lvl up a bit more and come back after some time, so you will "naturally" have better defence.
The third path is just use the yellow potion to shorthen the duration of bad status effects during the fights, so also if they stun you duration that will end fast.