fix error in my wordpress website

I've been having some issues with our wordpress site... for a month. It began giving me issues after posting a blog like I normally do only this time all kinds of problems occurred. For one it deletes all the text the second I hit save...if i try to add a new blog it kicks my site off line. AND I can not edit any text boxes anywhere on my site. If I do the entire text box also disappears. I also can no longer view TEXT in edit mode on front end or back end. I believe it has something to do with my MAIL CHIMP plug in but i can't say why or how this MAJOR ERROR began to occur. This is the message my hosting company said they could see. On my contact page my sign up box has also disappeared and i believe it has something to do this plug in. [10-Oct-2015 13:02:36 UTC] PHP Fatal error: Call to private MC4WP_Lite::__construct() from invalid context in /home1/thelovo4/public_html/wp-content/plugins/mailchimp-for-wp/mailchimp-fo [login to view URL] on line 58