To what extent your native language may be affected by attrition depends on many things. Most importantly, it depends on how old you were when you left your native country. To some extent, it may also depend on how old you are now, whether you are healthy or not, and how you feel about your native and your new language (and the culture that comes with it).
So, language attrition may affect different populations very differently, for example:
Language Attrition 