Yes, ever is necessary! If, you take out ever, you have and had. Which are the same word, except different tenses.
'Have had' is perfectly acceptable English. The question is, does 'ever' add any meaning to the sentence. In my opinion, 'in my life' is rather inclusive so 'ever' adds nothing.
Bryan is right.
if we say " It's the worst I have had in my life" the sentence is grammatically correct but since we're using the supperlative then it is preferable -some how necessary- to add "ever" inorder to insist on the supperlative so that the sentence would be: It's the worst I have ever had in my life.
ps: the verb to have is used in the present perfect tense ---> have had
Ever is unnecessary here as we already have 'in my life' in this sentence, the word 'ever' adds nothing.
Using the word 'ever' gives extra 'action' to the statement especially if emphasis if put on it. It's the worst I have EVER had in my life. Whereas if you are just stating a fact without punch, it's perfectly okay to say, "It's the worst I have had in my life"
I agree with Patti!