How to get my girl friend to trust me?

We have been dating online for 3 months and its like she has no trust for me what so ever puts nothing past me we are supposed to meet RL this weekend. shes only a short distances away ive know her over a year online. Im not some blind dumb 14 yo kids im 19 and sure i can handle it its in my local area. Im also accused of having **** loads of drama when i dont even tell her if i have the slightest anymore due to her changing when i did a favor for my online ex who did me dirty in game (second life). I have told her about my bad breakups with 2 current ex's and she says i do seem the be negative about anything like the day someone annoying me like i complain alot ect. we are close to falling out i dont wana loose this girl for anything she makes me feel so comfortable and i trust her even as i do have trust issues. So how can i get her to see past the past, the "drama" and to trust me more.