When you have sex with someone you don't love, you feel bad afterwards. You feel lost and wrong. You will realize you have been looking for something in the wrong place and you have been cheated, by the man you had sex with and by yourself. It is hard to realize this point.
Sex is necessary, but not indispensable. If you can not find a man you love, you can have sex with a man you trust, then let go all your fear and tension. You respect each other and be open to each other. Give total love to each other while you are together. When it finishes, just leave everything as it is until next time. Be peaceful. Desire is the pain that your desire can not be fulfilled. When you are peaceful, the pain will be less, the desire will be less.
If you can not find a man you can trust, find a man who is really stupid and humble. You use him as a tool to release your tension. But having sex with a stupid man is not much better than masturbating using a sex toy.