How do I overcome this mental block?

I am hesitant in learning a new language because I already forgot one I learned.

Up to 7 years ago I was hold to able basic conversation in french, I even went and did the 1 week host family thing with school and found no difficulty in communicating. I now remember <10 words, and forgot how to speak it in less then a year after I stopped studying it.

So would I constantly have to upkeep a new language I learn? That's disheartening. What's your experience?