How to fix strange behavior of vertexes? (picture) I cant understand the reason why this two vertexes move like if they are linked.
If I move one, the other moves too in a different direction, if I change the weight of one, weight of the other changes to opposite.
Please, someone, help to fix this!
Your vertices are weighted on bad bones.

The selected vertex should have 1 for Bone1.035 and nothing else. This can be seen in Edit mode in the N panel. From there you can change the weight values (in this case, 1 for Bone1.035 and remove with X bone3.044).
The other vertex needs to have only bone3.044.
Once this is done, place your vertices where they should be and they'll do what you expect.

You're life would be easier with better bones names (Something like Arm1.bone1, arm1.bone2, Arm2.bone1 ...)