.... I'm stuck in a really rough spot..

How do you move on from a five year relationship and still married but separated....??? I need to know... This whole thing is stressful and I feel like my mind is going to break... The stress over the past six months was terrible and I lost almost over 100 pounds( I was 210 before all the stress). I'm scared I don't know what or how to think right now. All I say now is I don't know. I can't think straight.