<human>: Can you provide a brief overview of the text?

Me and my girlfriend have been seeing each casually for about 3 months, we became an official couple close to 3 weeks ago. I am having a general distrust towards her. She has slept around a lot, and slept with a couple of people before were official during the period of our casual dating. She has cheated on all of her previous boyfriends, and has a promiscuous past. 

The craziest part is I like her a lot despite knowing all of this; she is very talented, interesting, beautiful, we have a lot of fun together, have a great sex life, and we make music together which for me is magical. We have both already said "I love you", her being the first, and I didn't say it back for about a week or two. 

I have trust issues with her that I have expressed with her, and she is saying she won't ever cheat on me, and how much she loves me. I believe her, and if she did cheat on me I wouldn't take it as she doesn't love me, but more of she isn't capable of having a serious relationship because of her state of mind. I am asking her to start therapy as well to explore her past traumas, and find healing. She has started going to church regularly, and is in some intense church "therapy" program. She also has been reading some relationship books that I let her borrow that help define and manifest healthy relationships in her life.

 I am very supportive of her growth, and I want her to be whole and healthy in this relationship. I care about her a lot, but the closer I get to her, the more the idea of her cheating on me eats me up. I have a good sense when she is being honest, and I believe her to love me and I believe she is doing her best in terms of what she is working with. I want to know what I should do... 
To be honest I want to give her a fair shot because care about her a lot, and this being a huge block in front of possible fantastic relationship, but I don't want to lose myself to frustration and fear in the process. How do I move forward without letting my fears and insecurities eat me alive?
<bot>: Girl has sexual promiscuous past, and is trying to change. I love her, and am supporting her in that change. How do I move forward on this path without letting my fears & insecurities eat me alive.