Learning a language

For a while now, I've been saying that I want to learn Polish. Not just to understand some of the music I listen to, but because in a few years, I hope to travel there and would like to be able to converse a bit to ensure I'm not served a plateful of kielbasa.

The problem is, I've never really been that great at learning languages. I did OK in high school and college French, but I don't remember anything but curse words and really only had barely passable knowledge at my best. That's why I'm a bit dismayed at this post that explains why Polish may be the most difficult language to learn:

I've read about the supposed difficulty of many languages. Some I don't know at all (like Chinese or Arabic, which I'd imagine are difficult), but I did have the opportunity to learn one of the hardest, and supposedly the most grammatically-complex Slavic language, Polish. It is certainly harder than Croatian, which I already knew when I started to learn Polish.

Here's one (somewhat trivial, but illustrative) example of the relative complexity of languages: the number 2.

English, Spanish, Dutch: 1 form (two, dos, twee)

Portuguese: 2 forms (dois/duas) - depending on gender (2 - masculine & feminine)

Croatian: 7 forms (dva, dvije, dvoje, dvojica, dvojice, dvojici, dvojicu) - depending on gender (3 - masculine, feminine, and neuter) and case in one specific form. There were other variants historically but they're not used anymore.

Polish: 17 forms. Depends on gender (3), case for all forms. Pretty much all these forms occur in regular speech (6-11 less often than the others)

Yikes. I had enough time remember if it was "la chaise" or "le chaise"... but 17 forms of the number two?

I think I'm in trouble.