Trust issue. Suggest me to resolv!

When I was young I have gone through sexual harassment which no one know till date because of it I was mute (speak less and hard to mingle in group) had hard childhood and poor family background. I became mentally matured in young age and start observing thing without taking part in any started acting like invisible person. Never thought of dressing pretty to impress others thinking others will sexually harass me. I am quite innocent which I don't like to be so started avoiding people thinking they will take advantage of me now. I do have few friends. I do let them take advantage but I'm really having problem to trust any I can't have a relationship and a good friend circle due to trust issue most of the time I'll be spending alone but I'm fine being alone I don't show any mentally ill nature, I'm good when I'm alone but I'm quite weird when I'm surrounded by peple I feel like I belong to other world. As per my observations I need to work on trusting others. please suggest me to resolv