UngeheuerLich
Legend
You have no chance to keep up if there is only a single fight per day without short rests. Your character profits mainly from short rests while the paladin mostly refreshes at long ones. The barbarian also. If your DM does not plan with short rests at all, and everyone can throw out daily resources at will I am sorry for you.
On the other hand, i am not sure if eldritch blast is your right answer to everything. With hex and hexblade curse and maybe eldritch knight you should be doing a lot more damage.
It is 2 beams at 1d10+1d6+8 damage and one extra attack at 1d8+1d6+8 damage. That averages to 47 damage without any problem. Use action surge and you should be ok.
On the other hand, i am not sure if eldritch blast is your right answer to everything. With hex and hexblade curse and maybe eldritch knight you should be doing a lot more damage.
It is 2 beams at 1d10+1d6+8 damage and one extra attack at 1d8+1d6+8 damage. That averages to 47 damage without any problem. Use action surge and you should be ok.