Scorp girl and Pisces boy....I need some help!!

Hi everybody! I need some help with a Pisces boy I am dating. We've been dating for 2 months now and we've been sleeping together. Initially, I had no problem trusting him but recently I have doubts about his intentions. I have a friend who is an aqua who is showing interest in me. But I totally just like him as a friend. This aqua friend is a big time player BTW. Well Aqua who knows well about playing suggested to check Pisces boy's phone. He said I will be surprised what I will find out LOL! So one night while Pisces and I were together, he accidentally left his phone in the bathroom. So out of curiosity I checked his phone. I found text messages from a girl which later I found out from Pisces that she was his ex. BTW Pisces doesnt know that I saw text messages to and from her. Anyway, Pisces said they were totally done since a year ago. One more thing, Theres a small picture of him and a girl posted on the wall in his room. Before it meant nothing to me but after I found out about the text messages, out of curiosity I asked Pisces about the girl and found out she was the ex gf. Now my questions: Do Pisces behave this way? Do you guys think he still has feelings for her? He admitted they still talk and see each other but only as friends. Whats up with the picture? do you guys keep pic of your ex displayed? His reasons they are still friends and its a nice pic of their trip. Should I ask him to take the pic down? I just feel his being disrespectful to me to have a pic of his ex posted on the wall in the room where we sleep together. Just want some insight if I should continue seeing this Pisces boy. I don't want to get caught in the middle incase they have some unfinished business going on! Thanks very much!

His chart: Birthday March 6

Sun Pisces 16.25
Moon Scorpio 10.19
Mercury Pisces 15.12 R
Venus Taurus 0.03
Mars Virgo 1.43 R
Jupiter Virgo 3.52 R
Saturn Virgo 24.13 R
Uranus Scorpio 25.33 R
Neptune Sagittarius 22.36
Pluto Libra 21.18 R
Lilith Virgo 26.50
Asc node Leo 29.14

My chart: Birthday Nov22

Sun Scorpio 29.45
Moon Aries 20.11
Mercury Sagittarius 18.12
Venus Scorpio 15.03
Mars Leo 8.58
Jupiter Cancer 4.47 R
Saturn Virgo 0.12
Uranus Scorpio 13.12
Neptune Sagittarius 15.17
Pluto Libra 15.46
Lilith Gemini 23.44
Asc node Libra 14.10

The texts were only replies from the girl...Dang!! I didnt know how to work his phone so I couldn get to his outbox messages. The text messages were something like these for what I remem

The texts were only replies from the girl...Dang!! I didnt know how to work his phone so I couldn get to his outbox messages. The text messages were something like these for what I remember:
1) I she your gf yet? ( could she be referring to me?)
2) I didnt know I supposed to pick you up. (Pisces went on a trip came back that day, sent me text messages and I assumed his ex too)
3) I remember you took me to that restaurant. (I guess they went there somewhere hahah)
4) Im just dating around I still have feelings for my ex ( could be Pices??IDK!!)
5) Thats what you wanted me to do right date other people? (Ya just date other people)
6) Im hanging out with friends its hard to text right now. (Maybe Pisces being pushy hahah)
7) I only reply to your text out of respect. ( What does she mean by this?)
8) How come you stopped asking me out? (maybe cause Pisces has me already ok stay away from him LOL)
9) Maybe we can do it when you get back. ( yah Pisces is back from his trip not sure what their planning to do tho)

Well those are some of them...I add more as I remember them..Thanks everyone!!!