Brad, it really seems like you"re totally lost on what you should be doing. What you should have done is exactly the opposite of what you did. Don"t insult her and the decisions she has made. Especially when those changes are permanent. It"d make anyone feel like shit. Plus, it really isn"t your place anymore. She also has the right to having a life outside of being a mom on the weekends just like you have that right. You should be lightly supportive when it comes to her personal life and her decisions. Especially if you want her back.
The renewed sexual contact from your ex is basically her looking to you for approval and possibly more. It seems like she was reaching out to you. She was proud of them, the boob job and the tattoo, and wanted to share them with you. She came to you. Think about it. That should raise an eye brow especially with your history. She still has feelings for you. Don"t you want to get back with her? Why would you even respond to her the way you did? To me, you sound like a child throwing a tantrum. Hopefully you can recover and try to bring her in instead of unconsciously pushing her away.
Regarding child visitation. You should always be on good terms with your ex-wife, the mother of your child, for specifically that reason, she"s the mother of your child. She has power, just like you have power, over the life of your child and how much you see him. Fortunately for you, your ex doesn"t seem like a nut case. If you really want to be in your child"s life more then you should propose a different change that would give you what you want and her what she wants, more time on the weekends.
If I read right, you see your son Monday - Thursday. How about sitting down with her and explaining to her what you want. Propose a compromise such as this example: Week 1, Mon. - Thurs. Week 2, Thurs - Sun. Week 3, Mon. - Thurs. Etc. That way you get to see your son more and she gets her weekends. See how she responds, then compromise calmly. Then apologize for being a dick about her tat and that you were just having a bad day. Tell her that you think it"s pretty neat even if you don"t think so. Come on man, this is your ex-wife. You should know this shit by now.
She still has feelings for you. Don"t be a dumb shit and fuck it up. Couple things to note if you"re trying to get back with her. Never fight with your ex, be calm. Never tell her about anything you"re doing with any other girls, it really isn"t her business plus it"ll sabotage you"re future together. You saw what happened last time you told her about the 19 year old. You guys basically already went on a date but you should ask her out again and see how she responds. Basically court her and romance her again. If she lets you court her again then it"s in the bag. The only one you"d have to blame for it not working out is yourself.