The correct usage for that sentence is the modal “may be,” as follows:
“We may be unaware of our own safety and feel that nothing can stop us.”
In the modal “may be”—with “may” separate from “be”—“may” functions as a verbal auxiliary to the verb “be” to express expectation of having, maintaining, or occupying a place, situation, or position.
In contrast, the word “maybe” is an adverb that means “perhaps.” To function properly, it needs to modify a verb, but we can see that there isn’t a corresponding verb in that other sentence you presented:
“We maybe unaware of our own safety and feel that nothing can stop us.”
For that sentence to work properly, it needs “are”—the plural form of the verb “be”—and must be reconstructed as follows:
“Maybe we are unaware of our own safety and feel that nothing can stop us.”
That sentence, of course, is the grammatical equivalent of the following constructions:
“Perhaps we are unaware of our own safety and feel that nothing can stop us.”
and
“We are perhaps unaware of our own safety and feel that nothing can stop us.”
