EXCLUSIVE

Yolanda Foster thinks she'll bounce back now that she's split from estranged husband David Foster.

Yolanda's been battling a severe case of Lyme disease, and sources say she's convinced it got worse when things got rocky with David. Lyme disease attacks the nervous system and stress is the enemy.

Our source says Yolanda constantly leaned on David during their marriage, but toward the end he was traveling a lot and she couldn't handle the change and got really sick as a result.

Now that they've pulled the plug on their marriage, she has no expectation that he'll be around, and that's actually dramatically improved her health.