Perfect Tense Stative verbs

Since you are talking about something which is still true, you need to use present perfect:

We use the present perfect:

• for something that started in the past and continues in the present:

They've been married for nearly fifty years.

She has lived in Liverpool all her life.

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(https://learnenglish.britishcouncil.org/english-grammar-reference/present-perfect)

Now let's return to your question. Sentences 2 and 4 are not what we need because we are talking about something which is still true, as we said (i.e. "I loved you" means "I loved you in the past, but now I don't"). Sentences 1 and 3 are perfectly fine.

Please note that present perfect can also be used in other situations. You can follow the link to the British Council site (or, perhaps, this link - https://www.englishpage.com/verbpage/presentperfect.html) for more details. Hope that helps!