If Muhammad never existed, how did his grave come to exist?

Ignoring the religious argument you opened up with your question lets answer it anyway. Graves are a shrine to the deceased. They are not always made with an actual body. For example in war a soldier may be know to be in a tent hit by artillery fire and there be no actual remains. A person can be a fisherman and lost at sea and still have a grave site for family to visit and mourn. Many nations have tombs of the unknown soldier for all the dead who were unrecovered from their conflict.

Can you ever completely stop loving someone and have no feelings for them if you did truly love them?

No I can't!We do get attached to the people easily but loving someone to the peak is a rare case.I know very well that I won't be able to get over my love because I will always push my limits for my loved one and that

I don't know why, but I always feel frustrated, feels like my life isn't going anywhere. What do I do?

I feel very similar myself. You know, if I had the chance, I would try to break out of the usual and try something really new, exciting, move to a big town where possibilities are endless and be a little