4 month old refuses to bottle/spoon feed???

I have a 4 mth old that absolutely WILL NOT take the bottle, and it's the most frustrating thing.... Even if my milk is in the bottle, she will hold the milk in her mouth, and spit it out.... She won't eat gerber jar foods either.... I'd like to ween her off my for when I want to go out, or maybe I might get sick?? But she refuses... I've already tried most of the tricks of the trade, such as mixing milk&formula.. I've tried putting the bottle nipple up to my own and feeding her that way... I've tried warming up the bottle to body temp so it would feel real... But none of it seems to be working! Any help?