Literally "I was lonely" or "I wanted to meet you".
I must own up to not answering this question because I wasn't sure what circumstances the various possibilities are suited for. Is "sabishikatta" equally good for a bloke you got drunk together in bars with as for a girlfriend? :?
For that matter I suppose if it's someone you want to say "I missed you" to then the plain form is generally (always?) the appropriate one. :relief:
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