How do I know if a girl I like also has feelings for me or if she is just being friendly with me? I really want to ask her out, but I am afraid of embarrassing myself if I read these signs incorrectly. I have been giving her a lot of hints about wanting to ask her to dinner, but none of them seem to make her say anything directly so I keep wondering if she is chatting with me because she wants me to say something specific. If this doesn’t work, I don’t know how I will be able to talk to her again. What should I do? How do I know what she’s thinking?
You won’t know what she is thinking until you ask her out because assuming you can read her mind will cause more harm than good. If she doesn’t want to go out with you, she won’t, and there’s nothing wrong with that because she has the right to agree or disagree. There’s nothing wrong with someone not reciprocating your feelings, and any perceived awkwardness that you believe will prevent you from speaking to her later is entirely up to you. Try approaching this with maturity and patience, accept that it’s okay for someone to not want to meet, and ask her out. The more direct you are, the sooner you will be able to figure out what to do next.

Are my concerns about my boyfriend’s past justified? He used to behave very badly with women, and I was warned, but he hasn’t said or done anything 
to worry me during the three months we have been together. Should I just be on my guard all the time?
There’s nothing wrong with being wary, but you should also be able to judge someone based on how they treat you in the present, rather than what they have done with other people in the past. If something bothers you, call it out. If it continues, you can rethink the future of your relationship.